Roles of free radicals, nitric oxide, and scavenging enzymes in nasal polyp development.

The aim of this study was to investigate the role of nitric oxide (NO), free oxygen radicals, and scavenging enzymes in the development of nasal polyp (NP) disease. This study included 41 patients who underwent endoscopic surgery because of NPs. Control specimens were taken from the inferior turbinate of 32 patients who underwent septoplasty. The levels of malondialdehyde (MDA), NO, and superoxide dismutase (SOD) were measured in intraoperative specimens of polyp tissue and turbinate mucosa. The levels of tissue NO were 191.06 +/- 26.62 micromol/mg of protein in patients with NPs and 145.30 +/- 19.19 micromol/mg of protein (p < .001) in the control group. The levels of MDA in the study and control groups were 12.47 +/- 2.12 nmol/mg and 8.83 +/- 1.08 nmol/mg (p < .01), respectively. The levels of SOD in the study and control groups were 50.77 +/- 14.74 U/mg and 77.93 +/- 15.31 U/mg (p < .001), respectively. It was determined that the levels of MDA in plasma and erythrocytes were higher in the patients with NPs than in the control group (p < .05). The levels of NO in plasma and erythrocytes in both groups were similar. The levels of SOD in plasma and erythrocytes were lower in patients with NPs than in the control group (p > .05). Increases in the levels of tissue MDA and NO and decreases in scavenging enzymes in patients with NPs as compared to control groups may indicate the presence of free radical damage in patients with nasal NPs. New studies are needed to clarify the efficacy of using antioxidants in the treatment of NPs.