8-isopentenylnaringenin and deoxypyridinoline

In order to examine whether 8-isopentenylnaringenin (1), which has been proven to possess estrogen agonist activity in in vitro tests, also produces in vivo estrogenic properties, the effects of 1 on uterus and on bone metabolism were determined in ovariectomized rats. Rats were ovariectomized and treated with 1 at 30 mg/kg/day subcutaneously for two weeks or 17 beta-estradiol at 0.01 mg/kg/day subcutaneously for two weeks. Ovariectomy resulted in an increase in urinary excretion of bone resorption markers (hydroxyproline, pyridinoline and deoxypyridinoline) and a decrease in bone mineral density of the proximal tibia as well as reduced uterine weight. Treatment with 1 or 17 beta-estradiol completely suppressed these ovariectomy-induced bone and uterine changes in a qualitatively similar manner. These results demonstrate that 1 acts as an estrogen agonist in the uterus as well as in bone in vivo.

Topics: Amino Acids; Animals; Biomarkers; Bone Density; Bone Resorption; Estradiol; Estrogens, Non-Steroidal; Female; Hydroxyproline; Isoflavones; Organ Size; Ovariectomy; Phytoestrogens; Plant Preparations; Rats; Rats, Sprague-Dawley; Tibia; Uterus