枸骨叶水提物对高脂小鼠胆固醇合成代谢的影响

Influence of Iiex cornuta extracts on constructive metabolism of cholesterol in high-fat mice

摘要:

目的  探讨枸骨叶水提物对高脂小鼠血清胆固醇水平及合成代谢信号通路的影响机制。方法  实验小鼠随机分5组，其中3组用高、中、低剂量枸骨叶水提物灌胃30 d后，测其血清总胆固醇（TC）、三酰甘油 （TG）、高密度脂蛋白胆固醇（HDL-c）和低密度脂蛋白胆固醇（LDL-C）含量，并与辛伐他汀组进行比较；采用酶联免疫吸附测定（ＥLISA）肝脏细胞中3-羟基-3-甲戊二酸单酰辅酶A还原酶（HMG-CoA）；采用蛋白质印迹法（Western blot）检测磷酸化表皮生长因子受体（p-EGFR）的表达。结果  枸骨叶高、中、低剂量组有降低TC的作用（P <0.01），与辛伐他丁组降低TC作用无差异；此外枸骨叶组均可降低HMG-CoA水平，降低肝细胞中p-EGFR的表达。结论  枸骨叶水提物对高脂饮食小鼠在清除TC方面发挥重要作用，它降低肝细胞中p-EGFR的表达，抑制HMG-CoA活性，进而降低高脂饮食小鼠体内TC水平而发挥降血脂作用。

Abstract:

Objective To evaluate the potential synergistic effect of Iiex cornuta or its essential component on serum cholesterol level and metabolism signal pathway of high-fat diet mice. Methods The mice were divided into 5 groups in random. Three groups took Iiex cornuta orally with different doses for 30 days. After that, serum total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were measured, and compared with those in Simvastatin group. The level of 3-hydroxy-3-methyl glutaric acid acyl coenzyme A (HMG-CoA) in liver cells was measured by ELISA. The expression of phosphorylated epithelial growth factor receptor (p-EGFR) in liver cells was detected by Western blot. Results Serum total cholesterol was lowered in the Iiex cornuta groups with different doses (P < 0.01). This effect was similar to that of the Simvastatin group. In addition, the HMG-CoA level obviously declined in the Iiex cornuta groups. The p-EGFR expression in the liver cells of the Iiex cornuta groups decreased compared to that of the control group. Conclusions Iiex cornuta plays an important role in clearing serum total cholesterol in the mice of high-fat diet. It can lower the expression of p-EGFR, inhibit the activity of 3-hydroxy-3-methyl glutaric acid acyl coenzyme A in liver cells and then reduce serum total cholesterol in the high-fat diet mice.