The Changes of the Generation of Superoxide Free Radical and the Activity of Antioxidant Enzymes after Streroid Therapy in Nasal Polyps

Cho, Jin Hak; Kim, Hyun Ung; Kim, Hee Dong; Oh, Won Hee; Jung, Yin Gyo; Chung, Keun; Lim, Hyun Joon

Abstract

BACKGROUND AND OBJECTIVES
An intranasal topical and a systemic steroid therapy produce clinical improvement in patients with nasal polyps, but the mechanisms of their action are not clear. Recently, reactive oxygen species such as oxygen free radicals were identified as the potent toxic agents in various pathologic conditions including nasal polyps. The purposes of this study were to reveal the steroid effect on the generation of oxygen free radicals and exmaine the activities of various antioxidant enzymes in human nasal polyps.
MATERIALS AND METHODS
Forty patients who received endoscopic sinus surgery due to chronic paranasal sinusitis with nasal polyps were classified into four groups; Group I included 10 specimens with no medication, group II included 10 specimens with oral steroid medication, Group III included 10 specimens with intranasal topical steroid therapy, group IV included 10 specimens with both oral and intranasal topical steroid therapy. We measured the generation of oxygen free radicals and activity of antioxidant enzymes, (SOD, GSH-Px, and CAT) and compared each group using electrophotometric analysis.
RESULTS
The generation of oxygen free radicals were lowered in group II, III, and IV, compared to group I. Group IV showed the lowest level in the generation of oxygen free radicals. The activities of SOD, GSH-Px, and CAT, which are specific scavengers of oxygen free radicals, increased significantly in groups II, III, and IV (p<0.05).
CONCLUSION
These results suggest that oxygen free radicals may play an important roles in the formation of nasal polyps. The mechanism of steroid action in the treatment of polyps may be explained in the decreased generation of oxygen free radicals and the increased activity of antioxidant enzymes in some ways.