Effect of Inhalation of Penicillium conidia on Worsening the Allergic Asthma in Murine Model

Modern lifestyle of societies, and living in small houses or apartments, make the allergen-sensitive individuals to be predisposed to allergic asthma following challenge with environmental allergens such as fungal spores. The air-borne fungal conidia can be a major contributor to allergic asthma in children. Therefore, in this study, we aimed to study the effect of exposure to fungal conidia on asthma in an animal model. Twenty-four Balb/C mice were divided into four groups (n=6) as followings: the asthmatic mice, the asthmatic and fungal spore (Penicillium chrysogenum)-exposed mice, the asthmatic and spore-exposed mice that is also treated with an antifungal drug (nystatin) and the healthy mice (PBS-treated mice). After the last administration on the day 31, bronchoalveolar lavage (BAL) fluid and tissue samples of lung were obtained. The gene expression of interleukin 4, 5 and 13 and pathologic changes in lung tissue of mice were investigated. The mRNA expression of the interleukin genes, perivascular and peribronchial inflammation, mucus secretion and goblet cells hyperplasia were increased in asthmatic mice that is also exposed to fungal spores in comparison to the asthmatic but not spore-exposed mice. Nystatin treatment in asthmatic and spore-exposed mice caused notable decrease in pathologic changes in lung tissue and mRNA expression of IL-4, 5 and 13. Antifungal treatment is recommended in asthmatic patients that also have high chance to be exposed to fungal spores. The results indicated that fungal spores are potential stimulators of allergic asthma so it is suggested that allergen-sensitive patients particularly children and those with the allergy history avoid any exposure with air-borne fungal spores.