Changes of antioxidant enzyme activity and heat shock protein content in lymphocytes of children with asthma

The aim of the present study was to examine whether changes in the antioxidant status and expression of major intracellular stress proteins are associated with pathophysiology of childhood asthma and severity of the disease. The activities of copper/zinc (CuZn) and manganese (Mn) superoxide dismutase (SOD) and catalase (CAT) in peripheral blood mononuclear cells (PBMCs) of 28 stable pediatric patients (11 mild persistent and 17 moderate persistent asthmatics) and 12 healthy children were assessed by native gel assays. The levels of two heat shock proteins (HSPs), Hsp70 and Hsp90, were examined by quantitative Western blot analysis. Moderate asthmatics, in comparison to healthy children, displayed higher activity of CuZnSOD, while differences of MnSOD and CAT activity between the groups of patients were not found. The levels of Hsp90 and the inducible isoform of Hsp70 were increased in moderate asthmatics as compared to mild asthmatics and healthy children. The results demonstrate an imbalance in cellular antioxidant and stress response systems that may contribute to pathogenesis of childhood asthma, but are not necessarily related to severity of the disease.Cilj ove studije bio je da se ispita da li su promene antioksidativnog statusa i ekspresije glavnih unutar ćelijskih stres proteina povezane sa patogenezom astme i težinom ovog oboljenja kod dece. Aktivnost bakar/cink(CuZn)-i mangan (Mn)-superoksid dismutaze (SOD), i katalaze (CAT) u mononuklearnim ćelijama iz periferne krvi 28 dece sa stabilnom astmom (11 sa blagim i 17 sa srednje teškim oblikom bolesti) i 12 zdrave dece ispitana je enzimskim testom u nativnom gelu. Koncentracije dva ispitivana proteina toplotnog stresa, Hsp70 i Hsp90, određene su tehnikom kvantitativnog imunoblota. Pacijenti sa srednje teškom astmom pokazali su povećanu aktivnost CuZn-SOD upoređenju sa zdravom decom, dok razlike u aktivnosti Mn-SOD i CAT između ispitivanih grupa pacijenata nisu zapažene. Nivo Hsp90 i inducibilne izoforme Hsp70 bio je povećan kod srednje teških astmatičara upoređenju sa blagim astmatičarima i zdravom decom. Rezultati ukazuju da disbalans u ćelijskom antioksidativnom i anti-stres sistemu može doprineti patofiziologiji dečje astme, ali ne mora biti povezan sa težinom oboljenja.nul