Korean J Allergy.  1997 Sep;17(3):286-298.

Comparative study on the activation status of eosinophils in exerise- and allergen-induced asthma

• Koh YY
• Choi JH
• Park CH
• Lee SY
• Kim CK
• Jeong JH

Abstract

Exercise is one of the most ubiquitous triggers of acute bouts of asthma. Late asthmatic responses(LARs) have been described following strenuous exercise, as in allergen-induced asthma. However, most studies have reported that airway responsiveness is not increased after exercise, even in subjects with LAR to exercise. This suggests that LAR after exercise may not be associated with inflammatory changes in the airways. We have frequently seen asthmatic children whose complaint is that symptoms are exacerbated at night after strenuous daytime exercise. Furthermore, airway responsiveness to allergen was reported to increase after LAR to exercise. Therefore, it is crucial to know whether exercise can induce airway inflammation, as in allergen-induced asthma. As an indirect measure to investigate it, we measured the activation status of eosinophil granulocyte in the peripheral blood during the early and late phase of exercise- or allergen-induced asthma. Eight subjects who showed early asthmatic response(EAR) and LAR(group 1), or EAR only (group 2) to allergen (Dermatophagoides pteronyssinus) challenge were selected. Similarly eight subjects who showed EAR and LAR(group 3), or EAR only (group 4) to exercise were selected. Blood samples were drawn at baseline, the early phase, the late phase, and 24 hours after each stimuli. Eosinofphil cationic protein (ECP) was measured in the serum. Eosinophil granulocytes were separated and the production of leukotriene C4 (LTC4) from purified eosinophfis was measured after stimulation with the calciumionophore. Serum levels of ECP were unchanged at EAR after allergen or exercise challenge. In the dual responder to allergen (group 1), serum ECP level was elevated at LAR and 24 hours after allergen challenge, as compared with the baseline level. On the other hand, in the dual responder to exercise (group 3), it remained unaltered up to 24 hours after exercise challenge. Eosinophils at EAR after allergen or exercise challenge in each group generated the similar amounts of LTC4 as baseline values. In group 1, the production of LTC4 was slightly increased though not significantly at LAR, and significantly increased 24 hours after allergen challenge. In group 3, it was increased significantly at LAR, but restored to the baseline values at 24 hours after exercise challenge. These results indicate that not only allergen but also exercise can activate eosinophils in accordance with LAR. The present findings suggest that LAR to exercise may also have the potential to induce airway eosinophilic inflammation although its duration may be shorter than that of LAR to allergen. Therefore exercise should be understood not only as a triggering factor of bronchoconstriction but also as one that incites or deteriorates airway inflammation.

MeSH Terms

Asthma*
Bronchoconstriction
Child
Ear
Eosinophils*
Granulocytes
Hand
Humans
Inflammation
Leukotriene C4
Leukotriene C4