PURPOSE: IS offers a convenient way for measurements of eicosanoids. We aimed to compare the concentrations of eicosanoids in IS supernatants in stable asthmatics with AIA, ATA and healthy controls (HC).
METHODS: In IS we measured cysteinyl leukotrienes (cys-LTs), 8-isoprostane, prostaglandin E2 (PGE2), prostaglandin F2α (PGF2α), prostaglandin D2 (PGD2) and 9α,11βPGF2 (stable metabolite of PGD2) in 20 patients with AIA, 22 non-atopic, and 36 atopic aspirin-tolerant asthmatics and 20 healthy controls (HC). Stable, mild or moderate asthmatics were treated with fluticasone (median dose 200-250 mcg/day), whereas LABA (if administered) had been withdrawn for 24h. Cys-LTs were measured by ELISA, whereas other eicosanoids by GC-NI-MS.
RESULTS: Median IS concentration of cys-LTs (pg/ml) was higher in AIA (3 520) than in ATA (960), and it was significantly higher in AIA than in HC (600) (p<0.05). There was not significant difference between these values in ATA and HC. There were significant correlations between the sputum eosinophilia and the levels of cysLTs, but only in AIA and HC. Median 9α,11βPGF2 level (pg/ml) was 2-fold higher in AIA (24,5) and ATA (24) than in HC (10,4). Among other metabolites studied no differences were found.
CONCLUSION: The higher levels of LTs in IS in AIA patients in comparison to HC is in line with previous data on higher LTs in BAL in this type of asthma. Higher concentrations of 9α,11βPGF2 in AIA and ATA than in HC may suggest ongoing mast cell activation in bronchial mucosa of asthmatics subjects.
CLINICAL IMPLICATIONS: IS is valuable non-invasive method for monitoring eicosanoids levels in different types of asthma.
DISCLOSURE: Ewa Nizankowska, None.