Cimetidine as a scavenger of ethanol-induced free radicals

Alcohol. 1992 Sep-Oct;9(5):363-7. doi: 10.1016/0741-8329(92)90033-7.


Free radical generation and the mobilization of catalytic iron are important in the pathogenesis of alcohol-induced liver injury. Cimetidine is a free radical scavenger in thermal skin injury and cobra venom-induced lung injury, and was therefore investigated as a scavenger of ethanol-induced free radicals. In vitro cimetidine inhibited iron-mediated cleavage of DNA as well as the potentiation of such cleavage by bleomycin. Peroxidation of microsomes by xanthine-xanthine oxidase, acetaldehyde-xanthine oxidase, as well as by the addition of low-molecular weight iron chelates were inhibited (17-100%) by cimetidine (0.1-1 mM). Free radical generation due to ethanol in isolated rat hepatocytes was studied by measuring ethane and pentane production. Cimetidine (1 mM) significantly decreased ethane and pentane production due to ethanol: 1 mM (2.2 +/- 0.3 vs. 1.0 +/- 0.2 pmol ethane per 10(6) cells/h; p less than 0.01, 4.2 +/- 0.4 versus 1.6 +/- 0.3 pmole per 10(6) cells/h pentane; p less than 0.001). Similar inhibitions were observed in the isolated perfused liver. Studies of superoxide reduction of ferricytochrome-C as well as hydroxyl radical generation by Fe(+)+/EDTA/ascorbate revealed that cimetidine was an effective hydroxyl radical scavenger. In summary, in a variety of in vitro systems, as well as in isolated hepatocytes and perfused liver, cimetidine inhibits ethanol-induced free radical injury. These findings may warrant its investigation as a therapeutic agent.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cimetidine / pharmacology*
  • DNA Damage
  • Ethanol / toxicity*
  • Free Radical Scavengers*
  • Free Radicals
  • In Vitro Techniques
  • Iron / pharmacology
  • Liver / drug effects*
  • Liver / metabolism
  • Male
  • Rats
  • Rats, Sprague-Dawley


  • Free Radical Scavengers
  • Free Radicals
  • Ethanol
  • Cimetidine
  • Iron