Assessment of enhancement of peak bone gain by isoflavone enriched standardized soy extract in female rats

In a longitudinally designed study, we tested whether an isoflavone enriched soy extract (SE) stimulated peak bone gain in rats during growth and maturity so as to confer better bone conserving effect after ovariectomy with concurrent treatment discontinuation. Weaned female rats were given SE or vehicle for 12-weeks and bone parameters were recorded (baseline). One group was then ovariectomized (OVx) and the other group sham operated. Vehicle group after OVx was given 17β-estradiol (E2) or continued with vehicle (OVx + vehicle). SE group after OVx was given vehicle (SEV). After 12-weeks, all groups were killed (endpoint). At baseline, SE group had greater cortical bone parameters over control. At endpoint, SEV group displayed significant bone conservation which was comparable to OVx + E2 group. Data suggest that SE enhanced peak bone accrual that supported skeletal preservation post-OVx on a par with E2 supplementation, not withstanding SE withdrawal at OVx.