Changes In Serum Reactive Oxygen Species After Iodine-131 Treatment And Its Clinical Significance In Graves Disease

Objective:To evaluate changes of serum oxidative stress parameters of Graves disease patients before and after 131I therapy, and to explore the effects of vitamin C as an adjuvant drug in the treatment of Graves disease on the oxidation and anti-oxidation.Methods:We selected 50 patients (14 males,36 females, mean age 42.1±10.2 years) in Graves disease with newly diagnosed and received 131I treatment from April to August in 2009 in the first hospital of shanxi medical university, department of nuclear medicine. All patients were not treated with ATD therapy, associated with diabetes, severe vascular, liver or kidney disorders, and not used anti-oxidant drugs such as vitamin C and/or vitamin E during the past month. They were randomly divided into two groups,131I group (32 cases) and 131I+Vc group (18 cases), the latter one was also given oral Vc tablet by the way 0.2g/time,3 times/day for 3 months. Serum oxidation and anti-oxidant parameters including malondialdehyde (MDA), total antioxidant capacity (TAC), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) of all patients before and 3 months after 131I therapy were determined respectively. Another 18 healthy volunteers (F:M=13:5, Age=40.1±9.8 years) were selected as control.Results:(1) The serum MDA, SOD and CAT levels were significantly higher and the serum TAC and GPx levels lower in Graves disease than those in the control group (P<0.05).(2) Compared with those before treatment, the serum TAC, SOD and GPx activities increased after 3 months'treatment in both 131I group and 131I+Vc group(P<0.05), while MDA level was significantly lower only in the 131I+Vc group(P<0.05), and no significant changes were found in 131I group(P>0.05).(3) Compared with 131I group, the decrease in serum MDA level and the increase in GPx activity in I+Vc group were significantly higher after 3 months'treatment(P<0.05), however, the increasd levels of serum TAC, SOD and CAT activities were almost equal between the two groups(P>0.05).Conclusion:There was an imbalance between serum oxidation and anti-oxidation system in patients with Graves disease. The antioxidative activities were increased in compensatory at 3 months after 131I therapy, conventional oral Vc tablet after 131I therapy can be effective in reducing oxidative stress damage.