Eosinophil apoptosis in induced sputum from patients with seasonal allergic rhinitis and with asymptomatic and symptomatic asthma.

BACKGROUND: Eosinophilic inflammation is known to play an important role in the pathogenesis of allergic diseases. Apoptosis, a form of programmed cell death, is characterized by morphologic cell changes and leads to recognition and ingestion by macrophages. Apoptosis could be an important mechanism controlling the resolution of tissue eosinophilia. OBJECTIVE: This study was designed to investigate the presence of apoptotic eosinophils in induced sputum of patients with seasonal allergic rhinitis (SAR), when examined during natural pollen exposure and of patients with perennial asthma of different degrees of severity. METHODS: We recruited 11 patients with SAR to grass pollens, 26 patients with asymptomatic asthma (AA), and 18 patients with symptomatic asthma (SA). The severity of asthma was assessed by clinical scoring. Sputum was induced following a standard method and differential cell count was estimated. Eosinophils showing cell shrinkage and nuclear coalescence were classified as apoptotic. The number of apoptotic eosinophils was expressed as the percentage of total cells in sputum and as the proportion of apoptotic eosinophils relative to normal bilobed eosinophils ("apoptotic ratio"). RESULTS: We found the number of eosinophils in the SA group was significantly greater than that in the SAR and the AA groups (P < .001 and P < .0001 respectively). The number of apoptotic eosinophils in the AA group was significantly lower than that in the SAR group (P < .001) and in the SA group (P < .0001). The apoptotic ratio for eosinophils in the SAR group was significantly greater than in the AA group (P < .05) and in the SA group (P < .05). There was no difference in the apoptotic ratio between the AA and SA groups. CONCLUSIONS: This study confirms that apoptotic eosinophils are detectable in induced sputum of allergic patients. Further, the results of our study suggest that apoptosis could be an important mechanism in the control of acute eosinophilic inflammation in patients with SAR exposed to the sensitizing antigens. It appears that the apoptotic mechanism could be less effective in controlling tissue eosinophilia in asthmatic patients with chronic eosinophilic inflammation.

Effect of inhaled furosemide and cromolyn on bronchoconstriction induced by ultrasonically nebulized distilled water in asthmatic subjects.

BACKGROUND: Inhaled furosemide has been shown recently to produce a protective effect against bronchoconstriction induced by several indirect stimuli, including ultrasonically nebulized distilled water (UNDW). Since there is a close parallel between its experimental effects and those reported for cromolyn,/it has been suggested that they may share some common mechanisms of action. Their protective effect, however, has never been compared directly. In this study, therefore, we have investigated the ability of equal doses (30 mg) of inhaled furosemide and cromolyn to modulate bronchoconstriction induced by UNDW in a group of ten asthmatic patients. METHODS: Subjects with documented bronchial response to UNDW were enrolled in a randomized, double-blind, placebo-controlled study. Treatments were administered five minutes prior to increasing outputs of UNDW and the response was expressed as the provocative output causing a 20% fall in FEV1 (PO20, in mL/min) and as the output-response slope. RESULTS: Geometric mean PO20 increased from 1.53 to 4.05 mL/min (P < .0004) after furosemide. After inhaling the highest output of UNDW (5.2 mL/min), PO20 was not measurable in six of ten patients when pretreated with furosemide and in all patients when pretreated with cromolyn. This difference was statistically significant (P < .05). Geometric mean values of output-response slope significantly decreased from 13.6 to 2.97 after furosemide (P < .0001) and from 13.6 to 1.43 (P < .0002) after cromolyn. CONCLUSIONS: These results suggest that cromolyn has a slightly greater anti-reactive activity in UNDW-induced bronchoconstriction compared to furosemide.

Once daily intranasal fluticasone propionate (200 micrograms) reduces nasal symptoms and inflammation but also attenuates the increase in bronchial responsiveness during the pollen season in allergic rhinitis.

BACKGROUND: Fluticasone propionate aqueous nasal spray, a new topical corticosteroid, has been proved to be an effective treatment for seasonal allergic rhinitis. OBJECTIVES: We studied the effect of fluticasone propionate on nasal symptoms, circulating eosinophils, and nasal inflammation in patients with seasonal allergic rhinitis after high-load pollen exposure. Moreover, we examined its efficacy in preventing the increase in bronchial responsiveness to methacholine (PD20) during the pollen season. METHODS: We conducted a double-blind, placebo-controlled, parallel-group study in patients who had a history of allergic rhinitis in response to pollens of grass and Parietaria species and were living in northern Italy. After a run-in period of 2 weeks, 24 patients were treated with fluticasone propionate (200 micrograms, once daily), and 26 patients received matched placebo for 6 weeks, starting from the beginning of the pollen season. Assessment of efficacy was based on scores of daily nasal symptoms. Nasal lavage was performed at the end of the season, and differential cell count was expressed as percent of total cells. PD20 methacholine was measured at the beginning and end of the season and after the season had ended. RESULTS: Fluticasone propionate significantly reduced nasal obstruction, itching, and rhinorrhea. Eosinophils in blood (p < 0.01) and nasal lavage (p < 0.001) were also reduced. Moreover, fluticasone significantly attenuated the decrease in mean PD20 methacholine (from 1.95 to 0.89 mg) compared with placebo (from 1.38 to 0.37 mg: p < 0.01). After the season, no difference in PD20 methacholine was found between treatment groups. CONCLUSIONS: The results of this study indicate that fluticasone propionate is effective in decreasing nasal symptoms and eosinophil inflammation in patients with seasonal allergic rhinitis after high-load pollen exposure. Our results also demonstrate that treatment with fluticasone propionate partially prevents the increase in bronchial responsiveness provoked by the inhalation of seasonal pollens in allergic rhinitis.

Effect of intranasal azelastine and beclomethasone dipropionate on nasal symptoms, nasal cytology, and bronchial responsiveness to methacholine in allergic rhinitis in response to grass pollens.

BACKGROUND: We compared the effect of nasal azelastine (0.56 mg/day), nasal beclomethasone dipropionate (BDP, 200 micrograms/day) and matched placebo on seasonal symptoms, nasal cytology, and the increase in bronchial responsiveness occurring during pollen season in a group of subjects with history of allergic rhinitis to grass pollens only. METHODS: The study was completed by nine subjects in the azelastine group, 13 subjects in the BDP group, and 13 subjects in the placebo group. Treatments were randomly administered for 6 weeks. Each subject recorded daily nasal, eye and chest symptoms and additional treatment requirement for the entire pollen season. Each subject performed nasal lavage 4 weeks into the pollen season. Bronchial responsiveness to methacholine was measured before and 4 weeks into the pollen season. Response was expressed as provocative dose causing a 20% fall in forced expiratory volume in 1 second in micromoles. RESULTS: Azelastine-treated subjects had significantly fewer nasal symptoms during week 4 (p < 0.05), and BDP-treated subjects had fewer nasal symptoms during week 4 (p < 0.05) and week 5 (p < 0.05) compared with subjects given placebo. Both treatments significantly reduced the need for additional medications. BDP, but not azelastine, treatment significantly reduced the percent of eosinophils recovered in nasal lavage (p < 0.05). Neither azelastine nor BDP protected against the increase in bronchial responsiveness to methacholine occurring during the pollen season. CONCLUSION: We demonstrated that both azelastine and BDP are effective treatments for nasal symptoms of seasonal allergic rhinitis after 4 weeks of therapy. However, we were not able to demonstrate an antiinflammatory activity of nasally administered azelastine. Nasal therapy with azelastine and BDP did not block the increase in bronchial responsiveness to methacholine caused by seasonal allergen exposure.

Effect of inhaled furosemide and torasemide on bronchial response to ultrasonically nebulized distilled water in asthmatic subjects.

Inhaled furosemide has been shown to reduce the bronchoconstriction induced by several indirect stimuli, including ultrasonically nebulized distilled water (UNDW). Because the protective effect could be due to the inhibition of the Na(+)-2Cl(-)-K+ cotransport system of bronchial epithelium, we have compared the protective effect of inhaled furosemide with that of inhaled torasemide, a new and more potent loop diuretic, on UNDW-induced bronchoconstriction in a group of 12 asthmatic subjects. UNDW challenge was performed by constructing a stimulus-response curve with five increasing volume outputs of distilled water (from 0.5 to 5.2 ml/min) and the bronchial response expressed as the provocative output causing a 20% fall in FEV1 (PO20UNDW). On different days, each subject inhaled an equal dose (28 mg) of furosemide and torasemide in a randomized, double-blind, placebo-controlled study 5 min prior to an UNDW challenge. Furosemide and torasemide had no significant effect on resting lung function. The geometric mean value of PO20UNDW measured after placebo was 1.73 ml/min. This was significantly lower than that recorded after furosemide (4.25 ml/min; p < 0.025), but not after torasemide (3.05 ml/min; p = 0.07). Inhaled furosemide totally blocked bronchial response to UNDW in five subjects. In two of five subjects the response was also blocked by inhaled torasemide. A remarkable increase in diuresis was noted only after torasemide in most subjects. We conclude that inhaled furosemide has a better protective effect than does inhaled torasemide against UNDW-induced bronchoconstriction. However, the protective effect of furosemide is variable, with some asthmatic patients showing no change in bronchial response to UNDW.(ABSTRACT TRUNCATED AT 250 WORDS)