Protective effect of 17beta-estradiol on oxidative stress and liver dysfunction in aged male rats

J Physiol Biochem. 2007 Sep;63(3):195-201. doi: 10.1007/BF03165782.


In aging liver oxidative stress increases due to the decrease in antioxidant bio-molecules such as estrogens which can be modified by hormonal replacement therapy (HRT). With this in mind, we hypothesized that age-related decline in steroidogenesis may be associated with the impairment of the antioxidant defense cells in liver, the increase in lipid peroxidation, hepatic dysfunction and histological changes; estrogens prevent all these changes induced by aging. 17beta-estradiol treatment was initiated in 12 month-old Wistar rats, and continued until 18 months of age. Our results showed that 17beta-estradiol (E2) level in the serum of the aged untreated rats was reduced by -32% in 18 month-old rats compared to the young animals (4-month-old). The superoxide dismutase (SOD), catalase (CAT), and gluthatione peroxidase (GPX) activities were reduced by -47, -46, and -29% respectively in old rat liver. In addition, the TBARs in liver and hepatic dysfunction parameters in plasma such as gamma-glutamyl transferase (GGT), phosphatase alkalin (PAL) as well as bilirubin level increased significantly in old rats, and histological changes were investigated. In E2-treated rats, protective effects were observed. Indeed, 17beta-estradiol attenuates all changes induced by aging. The 17beta-estradiol level was higher in old E2-treated rats compared to the control rats. Moreover, the SOD, CAT and GPX activities were higher by +28, +15, and +11% respectively. This anti-aging effect of estrogens was clarified by a lower level of lipid peroxidation and liver dysfunction parameters as well as by histological observation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / physiology*
  • Alkaline Phosphatase / metabolism
  • Animals
  • Bilirubin / metabolism
  • Catalase / metabolism
  • Estradiol / blood
  • Estradiol / pharmacology*
  • Glutathione Peroxidase / metabolism
  • Liver / anatomy & histology
  • Liver / drug effects*
  • Male
  • Organ Size
  • Oxidative Stress / drug effects*
  • Rats
  • Superoxide Dismutase / metabolism
  • Thiobarbituric Acid Reactive Substances / metabolism
  • gamma-Glutamyltransferase / metabolism


  • Thiobarbituric Acid Reactive Substances
  • Estradiol
  • Catalase
  • Glutathione Peroxidase
  • Superoxide Dismutase
  • gamma-Glutamyltransferase
  • Alkaline Phosphatase
  • Bilirubin