Effects of genistein and daidzein on cholesterol metabolism in ovariectomized rats

AIM: To study effects of genistein and daidzein on cholesterol levels in serum of ovariectomized rats. METHODS: 70 Wistar rats were randomly divided into 7 groups: control group, model group, estrogen group, genistein groups of high dose and low dose, daidzein groups of high dose and low dose with 10 rats in each group. All rats were ovariectomized except for that of the control group. One week after operation, the soy-isoflavones were administrated with different dose of genestein and daidzein for 6 weeks. Six weeks after operation, the rats were killed, with serum and liver taken, and the levels of total serum cholesterol (sTC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and total liver homogenate cholesterol (hTC), were measured. RESULTS: The level of sTC, hTC, LDL-C in serum of ovariectomized rats of model group increased significantly, compared with control group. Eestrogen reduced the levels of sTC, hTC and LDL-C, but had no effects on the levels of the HDL-C. Genistein reduced the levels of sTC, hTC and increased the level of the HDL-C, but had no effect on that of LDL-C. Daidzein reduced the levels of sTC, hTC, LDL-C, but had no effect on the level of the HDL-C. CONCLUSION: Genistein and daidzein suppressed the increase of cholesterol levels of serum in ovariectomized rats through defferent pathways. The effect of daidzein on serum cholesterol level of rats is more potent than that of genistein.