Soybean Isoflavones In Ovariectomized Mice Cognitive Function

Objectives: This study is to investigate the effect of soybean isoflavone on the cognitive function in ovariectomized female mice and it's mechanism.Methods: Eighty Kun-ming female mice, two months old, were randomly assigned into 5 groups: A(control)(sham operated); B(ovariectomized, OVX); C(OVX+50mg · kgbw-1·d-1 soybean isoflavone); D(OVX+150mg·kgbw-1·d-1 soybean isoflavone); E (OVX+450mg·kgbw-1·d-1 soybean isoflavone). Beginning from 7 days after surgery, the mice were treated intragastrically with soybean isoflavone or solvent once daily respectively for a period of two months, water maze and step-down test were tested during the middle and the end of the experiment. Serum SOD(superoxide dismutase), MDA(malonaldehyde), brain SOD , MDA , Na+K+-ATPase,Ca2+Mg2+-ATPase , AchE(Acetylcholinesterade) , MAO (monoamine oxidase) et al were measured.Results: Ovariectomy induced a significant decrease in serum SOD and brain Na+K+-ATPase, Ca2+Mg2+-ATPase; increased MDA of serum and MAO of brain; Which could be prevented by soybean isoflavone consumption. Moreover, soybean isoflavone could improve the cognitive function of ovariectomized female mice.Conclusions: Continuous oral administration of soybean isoflavone could improve the cognitive function of ovariectomized female mice, and the ability of anti-oxidation, the estrogen-like activation may contributed to the efficacy of soybean isoflavone to improve the cognitive function.