Antioxidant effect of short-term hormonal treatment in postmenopausal women

Objectives: Recent studies have shown that estrogens alone or in associatio n with progestins can exert an antioxidant effect on Low-Density Lipoprotei n (LDL) and lipids of platelet membranes. It has been demonstrated that the oxidative modification of LDLs also involving the formation of lipid perox ides, exerts several biological effects that may contribute to the onset an d progression of cardiovascular diseases. Therefore, the aim of our study w as to evaluate the effect of short-term treatment with oral estrogens alone and estrogens plus progestin on endogenous and copper-induced serum levels of lipid peroxides in postmenopausal women. Methods: Thirty-nine postmenop ausal women were randomly divided into three groups: group I was treated wi th oral conjugated equine estrogens (CEE) for 21 days; group II received or al CEE for 21 days and, after 14 days of this treatment, 5 mg/day of medrog estone was added for 7 days; group III did not receive any therapy (control s). Endogenous and copper-induced serum levels of lipid peroxides were dete rmined before and after 21 days of treatment in the two treated groups and in the control group. Results: The serum endogenous levels of lipid peroxid es in postmenopausal women did not change after short-term treatment with h ormone replacement therapy, Moreover, copper-induced serum levels of lipid peroxides significantly decreased after therapy in both groups I and II. Co nclusions: Our data show that hormone replacement therapy (HRT) inhibits li pid peroxidation and may play a role in preventing cardiovascular diseases. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.