ABSTRACT
The numbers of eosinophils and mast cells expressing 5-lipoxygenase of airway in aspirin-induced asthma (AIA) increased. LTC 4 synthase, the terminal enzyme for cys-LT production, is overexpressed markedly in bronchial biopsy specimens of most patients with AIA. These characterized the unique airway inflammation of AIA which may illuminat the pathogenesis of AIA to some extent.
ABSTRACT
BACKGROUND: Aspirin/NSAIDs can release cysteinyl-leukotriene (cys-LTs) into airways and precipitate asthmatic symptoms in aspirin - induced asthma(AIA). It has been reported that there is profound overexpression of LTC4 synthase in their bronchial mucosa, compared to aspirin-tolerant asthma. Objective : We observed whether genetic polymorphism of LTC4 synthase may be predisposed to LTC4 synthase overexpression in AIA. Subject and METHOD: Forty - four AIA patients having positive responses on lysin aspirin bron choprovocation tests and 47 non - aspirin induced asthma ( non - AIA ) patients having negative challenges and 32 healthy controls were enrolled. The genotypes of the promoter LTC4 synthase gene ( A,C transversion ) were determined by polymerase chain reaction and restriction fragment length polymorphism ( RFLP ) method. RESULTS: LTC4 synthase promoter polymorphism ( A444C btransversion) was not significantly different between non - AIA and AIA patients (p>0.05). Conclusion These findings suggest that genetic polymorphism of LTC4 synthase promoter may not be predisposed to LTC, synthase overexpression in AIA.