六味地黄方通过上调肠道雌激素受体改善绝经后ApoE-/-小鼠脂代谢异常研究

目的?应用双侧卵巢去势的ApoE-/-小鼠建立绝经后脂代谢异常模型，探究六味地黄方(LW)能否通过调节肠道雌激素受体改善绝经后脂代谢异常。方法?正常饮食的C57/B6小鼠为对照组(n=6)，高脂饮食并接受假手术的ApoE-/-小鼠为假手术对照组(n=6)，高脂饮食并接受双侧卵巢去势的的ApoE-/-小鼠为模型组(n=6)，模型小鼠接受4.5?g/kg (n=6)或9.0?g/kg (n=6)的六味地黄方治疗90?d。生化法检测小鼠血清中总胆固醇（TC）、甘油三酸酯（TG）、低密度脂蛋白（LDL-C）及高密度脂蛋白（HDL-C）水平，HE染色检测小鼠肝脏脂质损伤，油红染色检测小鼠肝脏脂质堆积，免疫荧光染色检测小鼠空肠雌激素受体α（ERα）、雌激素受体β（ERβ）、ABCG5、ABCG8、PI3K p110β及p-AKT的表达水平，免疫化学染色检测小鼠空肠NPC1L1的表达水平，Western blot法检测小鼠空肠NPC1L1、ABCG5及ABCG8的表达水平。结果?六味地黄方可降低模型小鼠血清TC、TG及LDL-C水平，升高HDL-C水平（P<0.05~0.01）；同时，六味地黄方可显著降低模型小鼠的肝脏脂质损伤和脂肪堆积（P<0.05~0.01）。六味地黄方显著增加模型小鼠空肠内降低的ERα和ERβ水平（P<0.05~0.01）。六味地黄方显著降低模型小鼠空肠中NPC1L1的表达水平（P<0.05），并上调ABCG5和ABCG8的表达水平（P<0.01）。六味地黄方显著增加模型小鼠空肠内PI3K p110β及p-AKT的表达水平（P<0.05~0.01）。结论?六味地黄方可以显著改善绝经后ApoE-/-小鼠脂代谢异常，其机制与六味地黄方调节肠道胆固醇的吸收和外排有关。上调肠道雌激素受体表达和肠道PI3K/AKT信号可能是六味地黄方调节肠道胆固醇吸收和外排的机制。 

Liuwei Dihuang Formula Alleviates Abnormal Lipid Metabolism by Up-Regulating Intestinal Estrogen Receptors in Postmenopausal ApoE-/- Mice

OBJECTIVE?Establish a model of postmenopausal abnormal lipid metabolism in ApoE-/- mice by bilateral ovariectomy， and to explore whether Liuwei Dihuang formula (LW) can alleviate postmenopausal abnormal lipid metabolism by regulating intestinal estrogen receptors. METHODS?C57/B6 mice with a normal diet were used as the control group (n=6)， ApoE-/- mice with a high-fat diet and receiving sham operations were used as the sham-operated control group (n=6)， ApoE-/- mice with a high-fat diet and receiving bilateral ovariectomy were used as the model group (n=6)， and the model mice received 4.5?g/kg (n=6) or 9.0?g/kg (n=6) LW for 90 days. Biochemical method was used to detect the levels of TC， TG， LDL-C and HDL-C in the serum of mice， HE staining was used to detect liver lipid damage in mice， oil red O staining was used to detect liver lipid accumulation in mice， immunofluorescence staining was used to detect mouse the expression levels of ERα， ERβ， ABCG5， ABCG8， PI3K p110β and p-AKT in the jejunum of mice， immunochemical staining was used to detect the expression level of NPC1L1 in the jejunum of mice. Western blot was used to detect the expression levels of NPC1L1， ABCG5 and ABCG8 in the jejunum of mice. RESULTS?LW could reduce serum TC， TG and LDL-C levels， and increase HDL-C level in model mice（P<0.05， P<0.01）， moreover， LW could significantly reduce liver lipid damage and fat accumulation in model mice（P<0.05， P<0.01）. LW could increase the expression levels of ERα and ERβ in the jejunum of model mice（P<0.05， P<0.01）. LW significantly reduced the expression level of NPC1L1 in the jejunum of model mice（P<0.05）， and increased the expression levels of ABCG5 and ABCG8（P<0.01）. LW significantly increased the expression levels of PI3K p110β and p-AKT in the jejunum of model mice（P<0.05， P<0.01）. CONCLUSION?LW can significantly improve the symptoms of abnormal lipid metabolism in postmenopausal ApoE-/- mice， and its mechanism may be related to the regulation of the intestinal cholesterol efflux and absorption. The up-regulated expression of intestinal estrogen receptor and PI3K/AKT signal in intestine may be the mechanism that how LW regulates intestinal cholesterol efflux and absorption.