Oxidative stress in stable cystic fibrosis patients: Do we need higher antioxidant plasma levels?

Oxidative stress plays an important role in cystic fibrosis (CF). However, there is a lack of validated biomarkers of oxidative damage that correlate with the antioxidant needs of patients with CF. Objective: To investigate oxidative stress in stable pediatric CF patients and evaluate if vitamin supplementation may be tailored to individual needs and oxidative status. Results: Lipid-adducts 4-hydroxynonenal (HNE-L) and malonaldehyde (MDA-L) (chromolipids) were elevated in the majority of patients despite normal plasma vitamin E, A and C. HNE-L and MDA-L increased with age, while plasma vitamins decreased. The most relevant correlation was identified between vitamin C and chromolipids. Patients with pancreatic insufficiency (PI) showed significantly higher plasma chromolipids despite no differences in plasma vitamins. Conclusions: The majority of patients showed elevated plasma chromolipids that increased with age. Antioxidant vitamin reference ranges provide incomplete information on the redox status. CF patients with PI showed excessive oxidative stress damage.