Prolidase activity and oxidative stress parameters in patients with nasal polyps.

Background And Aim: Oxidative stress is believed to have a role in the development of nasal polyps (NPs). It is also known that prolidase activity increases secondary to chronic inflammation. The purpose of this study was to evaluate the association between prolidase activity and oxidative stress parameters in patients with NPs.

Materials And Methods: Sixty patients with NPs, septal deviations and the concha hypertrophies were recruited to the study. Patients were divided into two groups; group 1 (n=30) consisted of patients with NPs, and group 2 (n=30) included patients with septal deviations and concha hypertrophies. Polyp specimens were taken from all patients who underwent endoscopic surgery for NPs. Control specimens were acquired from patients who underwent an operation for septoplasty or concha hypertrophy. Blood and tissue samples were obtained to assess lipid hydroperoxide (LOOH), catalase (CAT) and prolidase activity.

Results: Compared to group 2, group 1 had significantly higher LOOH and prolidase levels, and lower CAT levels both in serum and tissue samples (p<0.05 for all). Prolidase activity was correlated with increased LOOH and decreased CAT levels (r = 0.507 p = 0.004; r = - 0.579, p = 0.001, respectively).

Conclusions: Our study demonstrated that oxidative stress and prolidase activity, both in serum and the tissue in patients with NPs, were higher than in patients without NPs.