Acute Effects of Beclomethasone on Hyperpnea-Induced Bronchoconstriction : Medicine & Science in Sports & Exercise

Journal Logo

CLINICAL SCIENCES

Acute Effects of Beclomethasone on Hyperpnea-Induced Bronchoconstriction

KIPPELEN, PASCALE1,2; LARSSON, JOHAN3,4; ANDERSON, SANDRA D.1; BRANNAN, JOHN D.1; DELIN, INGRID3,4; DAHLEN, BARBRO4,5; DAHLEN, SVEN ERIK3,4

Author Information
Medicine & Science in Sports & Exercise 42(2):p 273-280, February 2010. | DOI: 10.1249/MSS.0b013e3181b541b1
  • Free

Abstract

Exercise-induced bronchoconstriction (EIB) is prevalent both in patients with asthma (9) and in endurance-trained athletes (33). After strenuous exercise in either of these populations, there is a transient reduction in airway caliber, usually defined as a 10% reduction in forced expiratory volume in 1 s (FEV1) from the baseline prechallenge value (11).

The postulated mechanism for this change in airway caliber is the mediator's release in response to hyperpnea-induced increase in osmolarity of the airways surface lining fluid (2). In support of this concept, hyperosmolar challenge of human mast cells in vitro promotes release of its mediators histamine, prostaglandin (PG) D2, and the cysteinyl-leukotrienes (LT) (16). In humans, PGD2 is a potent bronchoconstrictor (4) that, almost exclusively, is produced by mast cells (12). As a consequence, its major urinary metabolite 9α,11β-PGF2 may be used to follow mast cell activation in vivo. Accordingly, urinary levels of 9α,11β-PGF2 are increased after allergen-induced bronchoconstriction (28) and EIB (29). Moreover, 9α,11β-PGF2 and LTE4 levels are increased after mannitol-induced bronchoconstriction as well as exercise in subjects with asthma and in athletes with EIB (7,26,31). It has been shown that 9α,11β-PGF2 is a more sensitive in vivo marker of mast cell activation than serum tryptase (5).

Chronic treatment with inhaled corticosteroids (ICS) can inhibit EIB in subjects with asthma (36). However, recent studies support that inhalation of single high doses of fluticasone (37), budesonide (15), and ciclesonide (14) may also blunt the bronchoconstriction induced by stimuli such as adenosine monophosphate (AMP), hypertonic saline, and exercise. Several hypotheses have been put forward to explain this rapid onset of action of ICS that clearly must be via a different mechanism than conventional activation of nuclear glucocorticoid receptors that require several hours for the production of key transcription factors.

Recruitment of the small airways into the conditioning of the inhaled air is thought to be an important determinant for severity of EIB (2), especially in those individuals able to generate high ventilatory flow rates during exercise such as endurance-trained athletes. Hydrofluoroalkane (HFA)-beclomethasone dipropionate (BDP) is a potent glucocorticosteroid with a small particle size that results in a greater deposition of the drug in the peripheral airways (23). These small airways have a high content of mast cells both in subjects with asthma and in healthy subjects (10). Consequently, we were interested to test whether a single high dose of HFA-BDP, given by inhalation, would inhibit the airway response to dry air hyperpnea and mast cell activation with release of inflammatory mediators in athletes with EIB and in subjects with mild asthma.

We hypothesized that the short-term improvement in airway reactivity to hyperpnea after an acute inhalation of 1500 μg of BDP would result from a reduced release of the inflammatory mediators 9α,11β-PGF2 and LTE4 in both populations.

MATERIALS AND METHODS

Subjects

Seven endurance-trained athletes with EIB (four runners and three triathletes) and eight untrained subjects with mild asthma, all nonsmokers, took part in this study (Table 1). Athletes trained at least 6 h·wk−1 (mean ± SEM = 10.8 ± 1.4 h·wk−1). Subjects' characteristics did not differ significantly between groups (Table 1). Six of the seven athletes reported a history of asthma in childhood and four acknowledged a medical history of EIB.

T1-8
TABLE 1:
Subjects' characteristics.

Subjects did not have a chest infection in the 4-wk period preceding the study. Every subject had a baseline FEV1 >80% predicted. Only one athlete and three untrained subjects with asthma were taking ICS on a daily basis. Atopy, as assessed by skin prick test, was found in all untrained subjects with asthma and in five of seven athletes with EIB. Mean immunoglobulin E (IgE) level was not significantly different between groups (Table 1). Informed consent was obtained, and all procedures were approved by the Central Sydney Area Health Service Ethics Committee (protocol no. X03-0164). During the study days, short-acting β2-agonists were withheld for 6 h, and nedocromil sodium or sodium cromoglycate was withheld for 48 h. Inhaled corticosteroids were not used on the days of the study. Long-acting β2-agonists were withheld for 48 h, whereas antihistamines and leukotriene (LT) antagonists were withheld for 7 days. All subjects were required to abstain from alcohol, caffeine, and niacin-containing drinks and food from 20:00 h the evening before the study, and no vigorous exercise was permitted for 24 h before each study day.

Study Design

To test the efficacy of a single dose of ICS, each of the subjects received a placebo aerosol in the morning of the experimental day 10 min before the bronchial provocation test with eucapnic voluntary hyperpnea (EVH) and 1500 μg of BDP (QVAR; 3M Pharmaceuticals, Loughborough, UK) in the afternoon 4 h before the second EVH test. Administration of interventions was done in a single-blind manner. The two EVH tests were performed 5.5 h apart, lung function was checked, and urine was collected 60 min before and 90 min after the challenges. Athletes attended the laboratory on two occasions (screening plus experimental day). The subjects with asthma, having been screened for asthma and allergy previously, came in only once for the experimental day.

Athletes' screening visit.

Subjects were queried on medical history of allergy and respiratory illness, family history of asthma, previous asthma or EIB diagnosis, current and previous medication use, and respiratory symptoms during or after exercise. Each subject had measurements of FEV1 performed in triplicate and repeated 10 min later to confirm stability. An EVH challenge was then performed and used as a surrogate for exercise to detect EIB. After challenge, maximal expiratory flow-volume (MEFV) curves were performed in duplicate at 1, 3, 5, 10, 15, and 20 min. If the fall in FEV1 was 10% or higher (18), the subjects were considered as having EIB and were invited to take part in the study. To check the atopic status of the subjects, skin prick tests were performed.

Experimental day.

Subjects were asked to drink a glass of water 1 h before the visit. On arrival to the laboratory, subjects did three MEFV loops, emptied their bladder, and provided a urine sample. They were then given a further 100 mL at hourly intervals through the day. Blood samples were collected at rest, and levels of total IgE and CAP dust mite were analyzed. After 60 min, subjects provided another urine sample and performed another three MEFV curves and then the placebo was administered. Subjects were instructed to take 15 long, slow inhalations and to hold their breaths for 10 s. Ten minutes after the first inhalation, MEFV curves were repeated. An EVH challenge was then performed based on the protocol of Argyros et al. (3). This required subjects to breathe a compressed dry gas mixture (4.9% CO2, 21% O2, and balance N2) at a target ventilation rate (30 times FEV1) for 6 min. Postchallenge measurements included MEFV at 1, 5, and 10 min after the challenge and, thereafter, at 10-min intervals for up to 90 min. Urine samples were collected at 30, 60, and 90 min after the challenge. Samples were stored without the addition of preservatives at −80°C in Australia and shipped to Sweden on dry ice where they were kept in −20°C freezers until assay. LTE4 and 9α,11β-PGF2 are stable in urine samples at −20°C for long periods (22).

Once evaluation after placebo was completed (i.e., 90 min after the end of the first EVH challenge), the subjects received the active drug (i.e., 1500 μg of QVAR) and had a 3-h rest. In the afternoon, 1 h before the second EVH test, subjects had to perform three MEFV loops and to provide a urine sample. After 60 min, subjects provided another urine sample and performed another set of three MEFV curves. As in the morning, an EVH challenge was then performed, the lung function was checked, and urine samples were collected during a 90-min period after the challenge (same time intervals as in the morning).

Lung Function Measurements

Before and after the EVH challenge, lung function tests were performed in accordance with the American Thoracic Society recommendations (1) using a SpiroCard® (QRS Diagnostics, Plymouth, MN). FEV1 and forced vital capacity (FVC) were measured in triplicate at baseline, and two measurements were performed after the EVH challenges. The equations of Quanjer et al. (30) were used for the calculations of predicted values. The values measured immediately before the start of the EVH test were taken as the prechallenge values and used to calculate the postchallenge fall in lung function.

Mediators Analyses

Enzyme immunoassay of 9α,11β-PGF2 was performed in serially diluted urine samples using a rabbit polyclonal antiserum and acetylcholinesterase-linked tracer (Cayman Chemical Company, Ann Arbor, MI) essentially as described previously (21,29). The antibody cross-reacted with 2,3-dinor-9α-11β-PGF2 (10%), 13.14-dihydro-15-keto-prostaglandin F (0.5%), and all other primary eicosanoid metabolites (below 0.01%). Analysis of urinary LTE4 was performed following a similar protocol (29) using a rabbit polyclonal antiserum directed against cysteinyl-LT (Cayman Chemical Company) with acetylcholinesterase-linked LTE4 as tracer. The specificity of the antiserum for LTC4 was 100%, for LTD4 100%, and for LTE4 67%. In six subjects (three athletes and three subjects with asthma), the levels of LTE4 were below the detection limit at occasional time points. In the statistical analysis, these were treated conservatively and set as the lower limit of detection value (i.e., 7.8 pg·mL−1). Creatinine analyses were performed using a modification of Jaffe's creatinine protocol (19). All urine samples were analyzed for creatinine, and the results are expressed as nanograms of excreted mediator per millimole of creatinine.

Atopic Status

Skin prick tests were carried out using standardized allergen extract against the following allergens: house dust, house dust mite, timothy grass, Alternaria, Aspergillus fumigatus, Aspergillus niger, cat, dog, perennial rye, and cockroach. A positive test result was a reaction with a wheal of ≥3 mm in diameter. Total IgE and specific IgE to dust mites were measured on venous plasma using the UniCAP Analyser machine (Pharmacia, Stockholm, Sweden).

Statistical Analysis

All data are presented as mean ± SEM unless otherwise stated. Two MEFV curves were obtained at each recovery time point after EVH, and the highest FVC and FEV1 were recorded. The maximum falls in FVC and FEV1 were the lowest FVC and FEV1 recorded after challenge expressed as a percentage of the baseline value recorded immediately before EVH. The area under the FEV1 time curve (FEV1-AUC1-90) was calculated from the percentage change from baseline FEV1 during the 90-min observation period by using the trapezoidal method. Protection afforded by BDP was calculated by subtracting the percent fall in FEV1 after BDP, from the value after placebo, and expressing it as a percentage of the placebo. The change in urinary excretion of 9α,11β-PGF2 and LTE4 after EVH challenge was calculated as the absolute change from baseline value (mean of the two samples collected during 1 h). The area under the 9α,11β-PGF2 and LTE4 time curves (9α,11β-PGF2-AUC1-90; LTE4-AUC1-90) was calculated from the absolute change from baseline values during the 90-min observation period by using the trapezoidal method.

Normality of the data was checked using a Shapiro-Wilk test, and homogeneity of variance was checked using the Levene test. Subjects' characteristics and baseline lung function were compared between groups using unpaired t-test or Mann-Whitney U-test (when appropriate). For differences between groups and treatments, repeated-measures ANOVA was performed. The source of any significant main effect was examined by the Bonferroni post hoc analysis. Linear regression tests (Pearson and Spearman correlation coefficients) were used to assess the association between lung function response to EVH and urinary mediators' release. The 0.05 level of significance was adopted for all tests. Statistical calculations were performed using the computer software SPSS 15.0 for Windows (SPSS, Inc., Chicago, IL).

RESULTS

Pulmonary function at rest.

Percent FVC predicted was the only spirometry data significantly higher at rest (first MEFV in the morning) in the athletic group compared with group of untrained subjects with asthma (108% ± 2% vs 100% ± 2%, P = 0.022).

Pulmonary function after treatment and before EVH.

Beclomethasone induced a small bronchodilator effect 4 h after administration (P = 0.009). The increase in FEV1 from pretreatment was 1.8% ± 1.3% in the athletic group and 3.7% ± 0.9% in the group of untrained subjects with asthma (compared with a decrease after placebo of 1.6% ± 0.6% in the athletic group and of 0.5% ± 0.9% in the group of untrained subjects with asthma).

Ventilation level during EVH.

The athletes produced a higher percentage of predicted maximum voluntary ventilation (defined as 35 times FEV1) values than the subjects with asthma (P = 0.008): athletes = 89.4% ± 2.8% and 89.0% ± 3.4% after placebo and active drug, respectively; subjects with asthma = 76.7% ± 2.0% and 78.4% ± 2.9% after placebo and active drug. There were no significant differences in the rate of ventilation achieved by either group during placebo (athletes = 120 ± 8 L·s−1, subjects with asthma = 100 ± 4 L·min−1) or BPD-treated sessions (athletes = 119 ± 8 L·min−1, subjects with asthma = 102 ± 6 L·min−1).

Pulmonary function after EVH.

BDP significantly inhibited the airway response to EVH in both groups (Fig. 1). Postchallenge maximal fall in FEV1 and FEV1-AUC1-90 were significantly reduced after BDP administration (P < 0.001 and P = 0.043, respectively; Table 2). The percent protection afforded by BDP on the maximum percentage fall in FEV1 to EVH was 34% ± 8% in the athletic group and 44% ± 8% in the group of untrained subjects with asthma (P > 0.05). BDP administration also significantly reduced the postchallenge change in lung volume: maximal fall in FVC was 7% ± 2% after placebo versus 4% ± 1% after BDP in athletes and 11% ± 2% after placebo versus 5% ± 1% after BDP in subjects with asthma (P = 0.005).

F1-8
FIGURE 1:
Mean (SEM) percentage change in FEV1 before (Pre) and after (Post) inhalation of placebo (circles) and BDP (triangles) and for 90 min after EVH in athletes (closed symbols) and subjects with asthma (open symbols). -, baseline values.
T2-8
TABLE 2:
Summary of main results.

Mediators' release.

Baseline urinary levels of 9α,11β-PGF2 (mean of the two samples collected during 1 h before EVH) differed neither between groups nor between treatments (Table 2). Baseline urinary LTE4 levels were however higher (P = 0.003) in the afternoon before the second EVH test compared with the morning before placebo administration (Table 2).

In association with the EVH-induced bronchoconstriction, there was an immediate increase in the urinary excretion of 9α,11β-PGF2 in both groups on the placebo day (P = 0.001; Fig. 2A). The difference was significant between rest and 30 min after challenge (P = 0.005) and between rest and 60 min after challenge (P = 0.04) in both groups. There was also a significant difference between the groups (P = 0.03); 9α,11β-PGF2 values being significantly higher at all time points in the subjects with asthma. None of these differences were observed after BDP (P > 0.05).

F2-8
FIGURE 2:
Mean (SEM) urinary excretion of 9α,11β-PGF2 (A) and LTE4 (B) at baseline (mean of the two samples collected during 60min) and during the 90-min period after EVH in the presence of placebo in athletes (closed symbols) and subjects with asthma (open symbols). *P < 0.05, versus baseline; £ P < 0.01, versus baseline and 30min after challenge only in the group of untrained subjects with asthma; & P < 0.05, versus subjects with asthma (at all times).

Post-EVH maximal change in 9α,11β-PGF2 was significantly reduced in both groups after BDP administration (P = 0.039; Fig. 3A). Further, BDP treatment significantly reduced 9α,11β-PGF2-AUC1-90 compared with placebo (P = 0.021; Table 2) with no significant difference between groups (P > 0.05).

F3-8
FIGURE 3:
Mean (SEM) maximal change (Δmax) in urinary excretion of 9α,11β-PGF2 (A) and LTE4 (B) after the EVH test in athletes and subjects with asthma after administration of placebo or 1500 μg of BDP. *P < 0.05, versus placebo.

Under placebo condition, LTE4 significantly increased between rest and 60 min after challenge (P = 0.014) and between 30 and 60 min after challenge (P = 0.008) only in the group of untrained subjects with asthma (Fig. 2B). None of these differences were observed after BDP (P > 0.05).

Post-EVH maximal change in LTE4 (Fig. 3B) was significantly reduced in both groups after BDP administration (P = 0.003). BDP also significantly reduced LTE4-AUC1-90 (P = 0.001; Table 2) with no significant difference between groups (P > 0.05).

Relationship between airway response to EVH and urinary mediators' excretion.

There was a significant correlation between the fall in FEV1 and the increase in urinary 9α,11β-PGF2 excretion after EVH (r = 0.544, P = 0.002; Fig. 4A). A similar association was found between FEV1 and LTE4 (r = 0.380, P = 0.038; Fig. 4B).

F4-8
FIGURE 4:
Correlations between the degree of bronchoconstriction after EVH and excretion of urinary 9α,11β-PGF2 (A) and LTE4 (B) in athletes (circles) and subjects with asthma (triangles) after administration of placebo (closed symbols) or 1500 μg of BDP (open symbols).

DISCUSSION

We found that a single high dose of inhaled BDP of 1500 μg had a rapid (i.e., within 4 h) effect on reducing the airway reactivity to hyperpnea with dry air in both trained athletes with EIB and untrained subjects with asthma with EIB. This confirms previous data obtained with high doses of other steroids in similar challenges (14,15,20,37). We extend this information by documenting that this inhibition of airway response was associated with a significant reduction in urinary excretion of the bronchoconstrictive mediators 9α,11β-PGF2 and LTE4. The findings provide a new perspective on the acute effects of inhaled BPD and further support that mast cells and their mediators play a role in EIB in both trained and untrained subjects.

Previous studies have investigated the effects of a single dose of ICS on airway hyperresponsiveness. Although no effect was observed when histamine was used as the bronchoconstrictive agent (20), a reduction in airway sensitivity to all stimuli that act indirectly by release of mediators was documented within hours of a single inhalation of ICS, i.e., AMP (14,20), hypertonic saline (15), and exercise (37).

We report for the first time that the severity of the percentage fall in FEV1 after a short period of hyperpnea of dry air is significantly related to the increase in urinary excretion of 9α,11β-PGF2 in both athletes and untrained subjects with EIB. 9α,11β-PGF2 is a major metabolite of PGD2 and the most sensitive in vivo marker of mast cell activation (12). Inhibition of the airway response to mannitol by the mast cell-stabilizing agent sodium cromoglycate is also associated with a reduction in the postchallenge rise in 9α,11β-PGF2 in urine (8). The release of 9α,11β-PGF2 was reduced after BDP administration in both of our study groups, and the postchallenge kinetic of 9α,11β-PGF2 excretion was similar between groups. This supports the proposal for mast cells and their bronchoconstricting mediator 9α,11β-PGF2 to be involved in the airway response to hyperpnea in both the athletic population and the untrained population with mild asthma with EIB.

The mechanism to explain the rapid effect (within 4 h) of a single high dose of ICS on airway caliber and mast cell mediator release is unclear. The significant reduction in urinary excretion of 9α,11β-PGF2 after BDP inhalation seems to occur faster than can be explained by genomic effects on nuclear glucocorticoid receptors. Further, there is no evidence to suggest that a single dose of ICS will reduce numbers of mast cells or alter their function (15). Likewise, it is established that glucocorticoids do not directly inhibit the biochemical reactions in the biosynthetic pathway for formation of LT (17), and an inhibitory effect on expression of cyclooxygenase enzymes catalyzing prostaglandin formation is also unlikely to be present within this short time frame.

We are rather inclined to interpret this rapid-onset effect of BDP in terms of actions on the airway microenvironment that interferes with the stimulus-response coupling that triggers hyperpnea-induced bronchoconstriction. For example, ICS are potent vasoconstrictors, and a significant reduction in airway blood flow has been demonstrated in both healthy subjects and subjects with asthma in response to this class of drug (25). The acute vasoconstrictor effect of the BDP could have counterbalanced the reactive hyperemia that follows hyperpnea reducing the airway response (24). However, vasoconstriction is unlikely to explain the whole magnitude of the effect because current data suggest that the vasoconstrictor effect of ICS is only transient (25). Another possibility is that the high dose of ICS inhibited the response to dry air hyperpnea and the release of mediators by changing the fluid balance in the airway wall, thereby reducing the osmotic stimulus within the submucosa. This concept is supported by recent evidence of a rapid nongenomic effect of glucocorticoids on the antisecretory response of airway epithelium (38). There is finally a possibility that the BDP may have inhibited mast cell release of mediators directly through a reduction in intracellular calcium as recently been reported in guinea pigs (39).

We reported a significant correlation between the release of LTE4 in urine and the severity of EIB, along with a reduction in the AUC1-90 of the post-EVH urinary levels of LTE4 after BDP inhalation in both our study populations. The finding of a late but sustained (60-90 min) release of LTE4 to EVH was, however, only significant in our group of untrained subjects with asthma. This supports the role of LT in sustaining the airway response to exercise in subjects with asthma (32). It also suggests that mediators, such as PGD2 and histamine, are important earlier in the response to exercise.

One new finding in this study is that athletes and subjects with asthma react qualitatively similarly with release of mast cell mediators in response to the EVH challenge. We cannot explain the quantitative difference, but presumably, this may relate to a greater extent of the chronic underlying inflammation in subjects with asthma. In contrast to PGD2 that is mainly produced by mast cells, cysteinyl-LT can also be released by many inflammatory cells including eosinophils. Athletes with EIB often present with a sputum neutrophilia, rather than an eosinophilia (6), which might contribute to a lower LTE4 release to the dry air challenge in the athletic group.

One limitation with our protocol was that the order of the two EVH tests was not randomized because both tests were performed on the same day. By administering the placebo first and in the morning, we avoided any carryover effect of BDP on the second test in the afternoon. However, we cannot rule out that, in some subjects, the reduction of the percentage fall in FEV1 after the second EVH test was partly explained by a refractory period or by a circadian effect. Refractoriness to successive exercise tasks (13) and EVH tests (35) is known to occur but usually lasts less than 3 h (13). With a 5.5-h interval between the two EVH challenges, it is likely that the refractory period had a very minor effect on our results. Circadian variation of the urinary mediators measured has been debated, but studies have failed to confirm the variation of LTE4 (22) or 9α,11β-PGF2 (27). Airway reactivity to various stimuli (e.g., histamine) is usually less pronounced during the afternoon, but this is not true for hyperventilation of cold dry air to which the airway response seems to be greatest in the afternoon (34). Hence, it is unlikely that, in our study, the difference in airway response to EVH after placebo and BPD was explained by diurnal variations.

In conclusion, this study demonstrates that a single high dose of BPD of 1500 μg has an acute beneficial effect on airway reactivity to hyperpnea of dry air in both athletes and untrained subjects with EIB. The increase in urinary excretion of 9α,11β-PGF2 and LTE4 was blunted 4 h after inhalation of BDP in athletes and subjects with asthma. Also, a significant relationship was found between the severity of the response to 6 min of dry air hyperpnea and the increase in urinary excretion of both 9α,11β-PGF2 and LTE4. The results of this study further support mast cell mediators as targets for the treatment of EIB in both summer sport athletes and untrained subjects with mild asthma.

The authors thank C. Perry for her technical assistance in preparing the article. This study was supported by grants from the National Health and Medical research Council of Australia and by the Swedish MRC, Heart Lung Foundation, Stockholm County Council (ALF), Vinnova, and Karolinska Institutet. The results of the present study do not constitute endorsement by American College of Sports Medicine.

No conflict of interest to declare by any of the authors.

REFERENCES

1. American Thoracic Society. Standardization of spirometry: 1994 update. Am J Respir Crit Care Med. 1995;152:1107-36.
2. Anderson SD, Holzer K. Exercise-induced asthma: is it the right diagnosis in elite athletes? J Allergy Clin Immunol. 2000;106:419-28.
3. Argyros GJ, Roach JM, Hurwitz KM, Eliasson AH, Phillips YY. Eucapnic voluntary hyperventilation as a bronchoprovocation technique. Development of a standardized dosing schedule in asthmatics. Chest. 1996;109:1520-4.
4. Beasley C, Robinson C, Featherstone R, et al. 9α,11β prostaglandin F2, a novel metabolite of prostaglandin D2 is a potent contractile agonist of human and guinea pig airways. J Clin Invest. 1987;79:978-83.
5. Bochenek G, Nizankowska E, Gielicz A, Swierczynska M, Szczeklik A. Plasma 9α,11β-PGF2, a PGD2 metabolite, as a sensitive marker of mast cell activation by allergen in bronchial asthma. Thorax. 2004;59:459-64.
6. Bonsignore MR, Morici G, Riccobono L, et al. Airway inflammation in nonasthmatic amateur runners. Am J Physiol Lung Cell Mol Physiol. 2001;281:L668-76.
7. Brannan JD, Gulliksson M, Anderson SD, Chew N, Kumlin M. Evidence of mast cell activation and leukotriene release after mannitol inhalation. Eur Respir J. 2003;22:491-6.
8. Brannan JD, Gulliksson M, Anderson SD, Chew N, Seale JP, Kumlin M. Inhibition of mast cell PGD2 release protects against mannitol-induced airway narrowing. Eur Respir J. 2006;27:944-50.
9. Cabral ALB, Conceição GM, Fonseca-Guedes CHF, Martins MA. Exercise-induced bronchospasm in children. Am J Respir Crit Care Med. 1999;159:1819-23.
10. Carroll NG, Mutavdzic S, James AL. Distribution and degranulation of airway mast cells in normal and asthmatic subjects. Eur Respir J. 2002;19:879-85.
11. Crapo RO, Casaburi R, Coates AL, et al. Guidelines for methacholine and exercise challenge testing-1999. Am J Respir Crit Care Med. 2000;161:309-29.
12. Dahlén S-E, Kumlin M. Monitoring mast cell activation by prostaglandin D2in vivo. Thorax. 2004;59:453-5.
13. Edmunds A, Tooley M, Godfrey S. The refractory period after exercise-induced asthma: its duration and relation to the severity of exercise. Am Rev Respir Dis. 1978;117:247-54.
14. Erin EM, Zacharasiewicz AS, Nicholson GC, et al. Rapid anti-inflammatory effect of inhaled ciclesonide in asthma: a randomised, placebo-controlled study. Chest. 2008;134:740-5.
15. Gibson PG, Saltos N, Fakes K. Acute anti-inflammatory effects of inhaled budesonide in asthma. A randomized controlled trial. Am J Respir Crit Care Med. 2001;163:32-6.
16. Gulliksson M, Palmberg L, Nilsson G, Ahlstedt S, Kumlin M. Release of prostaglandin D2 and leukotriene C in response to hyperosmolar stimulation of mast cells. Allergy. 2006;61:1473-9.
17. Gyllfors P, Dahlen S-E, Kumlin M, Larsson K, Dahlen B. Bronchial responsiveness to leukotriene D4 is resistant to inhaled fluticasone propionate. J Allergy Clin Immunol. 2006;118:78-83.
18. Hurwitz KM, Argyros GJ, Roach JM, Eliasson AH, Phillips YY. Interpretation of eucapnic voluntary hyperventilation in the diagnosis of asthma. Chest. 1995;108:1240-5.
19. Jaffe. Creatinine-Jaffe's method. Blood Safety and Clinical Technology. Guidelines on Standard Operating Procedures in Clinical Chemistry. [cited 2009 June 18]. Available from: http://www.searo.who.int/en/section10/section17/section53/section481_1755.htm.
20. Ketchell RI, Jensen MW, Lumley P, Wright AM, Allenby MI, O'Conner BJ. Rapid effect of inhaled fluticasone propionate on airway responsiveness to adenosine 5'-monophosphate in mild asthma. J Allergy Clin Immunol. 2002;110:603-6.
21. Kumlin M, Dahlén B. The challenge procedure influences the extent of allergen-induced urinary excretion of leukotriene E4. Clin Exp Allergy. 2000;30:585-9.
22. Kumlin M, Stensvad F, Larsson L, Dahlen B, Dahlen SE. Validation and application of a new simple strategy for measurements of urinary leukotriene E4 in humans. Clin Exp Allergy. 1995;25:467-79.
23. Leach CL, Davidson PJ, Hasselquist BE, Boudreau RJ. Lung deposition of hydrofluoroalkane-134a beclomethasone is greater than that of chlorofluorocarbon fluticasone and chlorofluorocarbon beclomethasone: a cross-over study in healthy volunteers. Chest. 2002;122:510-6.
24. McFadden ER, Lenner KA, Strohl KP. Postexertional airway rewarming and thermally induced asthma. J Clin Invest. 1986;78:18-25.
25. Mendes ES, Pereira A, Danta I, Duncan RC, Wanner A. Comparative bronchial vasoconstrictive efficacy of inhaled glucocorticosteroids. Eur Respir J. 2003;21:989-93.
26. Mickleborough TD, Murray RL, Ionescu AA, Lindley MR. Fish oil supplementation reduces severity of exercise-induced bronchoconstriction in elite athletes. Am J Respir Crit Care Med. 2003;168:1181-9.
27. O'Sullivan S, Dahlén B, Dahlén S-E, Kumlin M. Increased urinary excretion of the prostaglandin D2 metabolite 9α,11β-prostaglandin F2 after aspirin challenge supports mast cell activation in aspirin-induced airway obstruction. J Allergy Clin Immunol. 1996;98:421-32.
28. O'Sullivan S, Roquet A, Dahlén B, Dahlén S-E, Kumlin M. Urinary excretion of inflammatory mediators during allergen-induced early and late phase asthmatic reactions. Clin Exp Allergy. 1998;228:1332-9.
29. O'Sullivan S, Roquet A, Dahlén B, et al. Evidence for mast cell activation during exercise-induced bronchoconstriction. Eur Respir J. 1998;12:345-50.
30. Quanjer PH, Tammeling GJ, Cotes JE, Pedersen OF, Peslin R, Yernault JC. Lung volumes and forced ventilatory flows. Eur Respir J. 1993;6:5-40.
31. Reiss TF, Hill JB, Harman E, et al. Increased urinary excretion of LTE4 after exercise and attenuation of exercise-induced bronchospasm by montelukast, a cysteinyl leukotriene receptor antagonist. Thorax. 1997;52:1030-5.
32. Reiss TF, Sorkness CA, Stricker W, et al. Effects of montelukast (MK-0476), a potent cysteinyl leukotriene receptor antagonist, on bronchodilation in asthmatic subjects treated with and without inhaled corticosteroids. Thorax. 1997;52:45-8.
33. Rundell KW, Jenkinson DM. Exercise-induced bronchospasm in the elite athlete. Sports Med. 2002;32:583-600.
34. Sly PD, Landau LI. Diurnal variation in bronchial responsiveness in asthmatic children. Pediatr Pulmonol. 1986;2:344-52.
35. Smith CM, Anderson SD, Seale JP. The duration of action of the combination of fenoterol hydrobromide and ipratropium bromide in protecting against asthma provoked by hyperpnea. Chest. 1988;94:709-17.
36. Subbarao P, Duong M, Adelroth E, et al. Effect of ciclesonide dose and duration of therapy on exercise-induced bronchoconstriction in patients with asthma. J Allergy Clin Immunol. 2006;117:1008-13.
37. Thio BJ, Slingerland GLM, Nagelkerke AF, Roord JJ, Mulder PGH, Dankert-Roelse JE. Effects of single-dose fluticasone on exercise-induced asthma in asthmatic children: a pilot study. Pediatr Pulmonol. 2001;32:115-21.
38. Verriere VA, Hynes D, Faherty S, et al. Rapid effects of dexamethasone on intracellular pH and Na+/H+ exchanger activity in human bronchial epithelial cells. J Biol Chem. 2005;280:35807-14.
39. Zhou J, Lui DF, Liu C, et al. Glucocorticoids inhibit degranulation of mast cells in allergic asthma via nongenomic mechanism. Allergy. 2008;63:1177-85.
Keywords:

ASTHMA; EXERCISE; INHALED CORTICOSTEROIDS; MAST CELL ACTIVATION; LEUKOTRIENE E4; 9α; 11β-PROSTAGLANDIN F2

©2010The American College of Sports Medicine