Oxidative stress in ciliated nasal epithelial cells from patients with primary ciliary dyskinesia

Background: Primary ciliary dyskinesia (PCD) is a rare disorder characterized by dysfunction of respiratory cilia and impaired mucociliary clearance leading to recurrent airway infection and chronic inflammation appearing in childhood. Rationale and aims: Chronic inflammation has been associated to oxidative stress (OS). Moreover, evidence of increased OS in the airways of stable children with PCD has been shown (Zihlif, N. et al . Pediatr Pulmonol 2006; 41:509-14). We hypothesize that OS would be increased in ciliated nasal epithelial cells (CNEC) from patients with PCD. This study was aimed to assess the OS profile in CNEC isolated from children with PCD. Methods: CNEC were obtained from ten children diagnosed with PCD, ten PCD- like patients and ten control individuals. OS parameters were prospectively measured by flow cytometry. Results: PCD patients showed significantly higher reduced glutathione (GSH) (p=0.01) and total superoxide anion (O 2 - ) (p=0.03) but lower nitric oxide (NO) levels (p=0.05) than the control and PCD- like patients. PCD patients and PCD-like patients show higher oxidized/reduced lipid ratio (p=0.30), carbonylated proteins (CP) (p=0.14) and mitochondrial O 2 - (mO 2 - ) (p=0.16) than the control group although the results did not reach statistical significance. No significant differences were observed in mitochondrial parameters and H 2 O 2 between groups. Conclusions: PCD patients exhibit a pro-oxidant oxidative profile. PCD-like patients show a similar behaviour as PCD patients in levels of mO 2 - , NO, and CP, whereas a comparable behaviour to controls in total O 2 - and GSH levels. Our results suggest an implication of OS in the pathophysiology of PCD.