Effects of raloxifene on serum malondialdehyde, erythrocyte superoxide dismutase, and erythrocyte glutathione peroxidase levels in healthy postmenopausal women

Objective: To investigate the relationship between raloxifene administration and serum malondialdehyde (MDA), erythrocyte superoxide dismutase (SOD), erythrocyte glutathione peroxidase (GPx) levels in healthy postmenopausal women. Methods: In a randomized and placebo-controlled design, 80 women received either 60 mg/day raloxifene or placebo for 24 weeks. MDA, SOD, and GPx levels were assessed at 0,4,12, and 24 weeks. Wilcoxon signed-rank test and Mann-Whitney U test were used for comparisons. Results: Six women in the treatment arm and eight women in the placebo group discontinued the study. Mean serum MDA levels were significantly (p = 0.001) decreased from 11.4 nmol/ml at baseline to 8.9 nmol/ml at week 12 with raloxifene treatment. Mean erythrocyte SOD activity was significantly (p = 0.02) reduced from 1472 U/g Hb at baseline to 1173 U/g Hb at week 12 following raloxifene administration. Lowered serum MDA and erythrocyte SOD levels persisted during treatment. On contrary, erythrocyte GPx levels did not change significantly with raloxifene administration. Conclusions: Raloxifene (60 mg/day) lowers serum MDA levels and erythrocyte SOD activity in postmenopausal women after 12 weeks of treatment. The clinical implications of these findings need to be determined.