Treatment of pulmonary exacerbations of cystic fibrosis leads to improved antioxidant status

Many cystic fibrosis (CF) patients have increased circulating levels of oxi dation products and/or decreased antioxidant status. This study investigate d whether treatment of pulmonary exacerbations decreased oxidative stress i n CF patients. Seventeen adult patients were studied at the beginning and end of treatment with intravenous antibiotics. Plasma concentrations of the antioxidants as corbic acid, alpha-tocopherol, uric acid and total reduced thiols, together with plasma retinol, lipid hydroperoxides, malondialdehyde and protein car bonyl levels were determined. Median (interquartile range) pretreatment and post-treatment levels were compared using the Wilcoxon signed rank test. Clinical resolution was reflected by improved spirometry, Significant incre ases were observed in plasma ascorbic acid (pre 30.4 (15.7-38.6) mu M, post 35.2 (27.3-49.6) mu M), alpha-tocopherol (pre 19.7 (13.6-25.2) mu M, post 25.2 (19.3-31.6) mu M) and retinol (pre 1.9 (1.5-2.5) mu M, post 2.7 (1.7-3 .5) mu M). No change in plasma total reduced thiols occurred following trea tment (pre 409 (366-420) mu M, post 392 (366-423) mu M), whereas uric acid fell with treatment (pre 307 (274-394) mu M, post 260 (216-317) mu M). Neit her plasma protein carbonyls or malondialdehyde levels altered with treatme nt (protein carbonyls pre 0.47 (0.28-1.27), post 0.67 (0.42-0.83) nM.mg pro tein(-1); malondialdehyde pre 0.75 (0.53-1.18), post 0.84 (0.65-1.15) mu M) . Lipid hydroperoxides levels did decrease following treatment (53 (18-85) versus 17 (10-55) nM), This study demonstrated that treatment of infective exacerbations resulted in increased plasma levels of some antioxidant vitamins. No immediate chang e in plasma protein oxidation was observed, but lipid oxidation was decreas ed.