Antioxidant effects of estradiol and 2-hydroxyestradiol on iron-induced lipid peroxidation of rat liver microsomes

Steroids. 1994 Jun;59(6):383-8. doi: 10.1016/0039-128x(94)90006-x.

Abstract

In the present study, the antioxidant effects of estradiol (E2) and 2-hydroxyestradiol (2-OHE2) on microsomal lipid peroxidation induced by Fe3+/ADP/NADPH and Fe2+/ascorbate are described. The extent of lipid peroxidation was measured by thiobarbituric acid reactive substances (TBARS) detection, low-level chemiluminescence, and oxygen consumption. 2-OHE2 had a potent antioxidant activity, which in all cases was higher than that of E2. In the Fe2+/ascorbate model, 2-OHE2 showed a similar pattern of inhibition, irrespective of the presence of NADPH or the functionality of microsomes. However, E2 produced only a slight inhibition when either denatured microsomes or native microsomes without NADPH were used, whereas its protective effect increased considerably when microsomal E2 metabolism was favored. During enzymic Fe3+/ADP/NADPH-induced lipid peroxidation, both E2 and 2-OHE2 were found to provide good protection. Results underline the importance of the chemical structure of these compounds and the role of estradiol metabolism in its antioxidant effects.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antioxidants / pharmacology*
  • Estradiol / analogs & derivatives*
  • Estradiol / pharmacology*
  • Iron / pharmacology*
  • Lipid Peroxidation / drug effects*
  • Luminescent Measurements
  • Male
  • Microsomes, Liver / metabolism*
  • Oxygen Consumption / drug effects
  • Rats
  • Rats, Sprague-Dawley

Substances

  • Antioxidants
  • Estradiol
  • 2-hydroxyestradiol
  • Iron