大豆苷元对去卵巢大鼠血脂及肝脏ERα和LDLR表达的影响

Effects of Different Doses of Daidzein on Serum Lipids and Liver LDLR Expression in Ovariectomized Rats

目的:探讨不同剂量大豆苷元对绝经后血脂的保护作用。方法:选用4月龄SD雌性大鼠66只,随机分为:假手术组(Sham)、去势组(OVX)、戊酸雌二醇组(E2)、大豆苷元高剂量(H-Dai,200mg/kg)组、中剂量(M-Dai,50mg/kg)组和低剂量(L-Dai,10mg/kg)组,每组11只。于去势术后4周开始分别给予相应的药物灌胃,3个月后处死大鼠,取血和肝脏,检测血清甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-c)、高密度脂蛋白胆固醇(HDL-c),以及肝脏ERα和LDLRmRNA的表达量。结果:与OVX组相比,大豆苷元可以降低血清LDL-c,且随着剂量的增加其作用更明显(P<0.01);大剂量可以降低血清TG(P<0.05)。大豆苷元还增加肝脏ERα和LDLRmRNA的表达量,且也有剂量依赖效应,低、中剂量组与高剂量组差异显著(P<0.01)。结论:大豆苷元对去势大鼠血脂有一定保护作用,其降低血清LDL-c的作用可能是通过ERα途径增加LDLR的表达而实现的。

Objective： To explore the protective effect of daidzein with different dosage on serum lipids after menopause. Methods： Sixty-six Sprague-Dawley female rats aged 4 months were divided into six groups randomly （n = 11）. Four weeks later, Sham group and control OVX group were administreed with distilled water, whereas the other groups received valerate estriol （800 μg/kg） and different doses of daidzein （low dose, 10 mg/kg; medium dose, 50 mg/kg; high does, 200 mg/kg） by gavage for 3 months respectively. Serum TG, LDL-c, HDL-c and liver ERa, LDLR mRNA expression were measured after the sacrifice of the rats. Results： Compared with OVX group, daidzein could lower serum LDL-c（P〈0.01）, this effect in the high-dose group was more significant than that in the low-dose or medium-dose group, high-dose daidzein could lower serum TG （P〈0.05）. Daidzein increased ERa, LDLR mRNA expression in the liver, and the effect was more significant with the dose increased. Conclusion： Daidzein exerts some protective effects on serum lipids, the LDL-c-lowering effect may be attributed to the increase of LDLR expression, which may be realized through the ERα pathway.