These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Effect of dietary soy isoflavone aglycones on the urinary 16alpha-to-2-hydroxyestrone ratio in C3H/HeJ mice.
    Author: Kishida T, Beppu M, Nashiki K, Izumi T, Ebihara K.
    Journal: Nutr Cancer; 2000; 38(2):209-14. PubMed ID: 11525599.
    Abstract:
    Estradiol is metabolized through two mutually exclusive pathways. 2-Hydroxyestrone (2-OHE,) is antiestrogenic, while 16alpha-hydroxyestrone (16alpha-OHE1) is a potent estrogen. It is suggested that a high urinary 16alpha-OHE1-to-2-OHE1 rato is a biomarker of increased mammary tumor risk. Mice were fed one of the test diets for 21 days. Indole-3-carbinol (2,500 mg/kg diet) increased the cytochrome P-450 content of hepatic microsomes and liver weight and reduced the urinary 16alpha-OHE1-to-2-OHE1 ratio in comparison with the respective value in the control mice. Fermented soy extract (100, 200, or 400 mg isoflavonoid/kg diet), genistein (200 mg/kg diet), and daidzein (200 mg/kg diet) each reduced the urinary 16alpha-OHE1-to-2-OHE1 ratio without increasing the cytochrome P-450 content of hepatic microsomes or liver weight. The combination of genistein and daidzein (100 mg and 100 mg/kg diet) did not have a synergistic effect on the reduction in urinary 16alpha-OHE1-to-2-OHE1 ratio. These data suggest that the soy isoflavonoid aglycones genistein and daidzein and indole-3-carbinol each exert a cancer-preventive effect by shifting metabolism away from the production of genotoxic metabolites toward the production of inactive metabolites.
    [Abstract] [Full Text] [Related] [New Search]