RADIOIODINE TREATMENT AND OXIDATIVE STRESS IN THYROIDECTOMIZED PATIENTS FOR DIFFERENTIATED THYROID CANCERS

Post-operative radioiodine treatment of differentiated thyroid cancer occupies a well determined place in the treatment policy of this disea se. Since little is known about erythrocytes oxidant and antioxidant s tatus in patients with thyroid cancers after radioiodine, treatment, w e measured erythrocyte malondialdehyde (MDA) levels, as a marker of li pid peroxidation, erythrocyte reduced glutathione (GSH) levels and act ivities of GSH-Peroxidase and GSH-Reductase as antioxidants. We found that erythrocyte MDA levels were significantly higher, and erythrocyte GSH levels and activities of GSH-related enzymes were significantly l ower in thyroidectomised patients after surgery than in healthy contro ls. Additionally, according to their thyroid hormone levels the patien ts had hypothyroidism at this time. In patients 2 days after radioiodi ne treatment both MDA and GSH levels and GSH-related enzyme activities were significantly increased when compared to their own initial level s. In conclusion, we, suggested that radioiodine could facilitate or i nduce significant oxidant/antioxidant changes in erythrocytes-indirect ly as a result of the internal radiotherapy with radioiodine. (C) 1998 The Italian Pharmacological Society.