菝葜乙酸乙酯提取物对THP-1源性荷脂细胞胆固醇蓄积及SREBP-1表达的影响

目的： 观察菝葜乙酸乙酯提取物对人单核/巨噬细胞系（THP-1）源性荷脂细胞胆固醇蓄积的影响，并初步探讨类固醇调节因子结合蛋白-1（SREBP-1）蛋白表达在其中的作用。 方法： 以THP-1源性荷脂细胞为模型，洛伐他汀（80 mg·L^-1）做阳性对照，菝葜乙酸乙酯提取物不同浓度（0，40，80，160 mg·L^-1）作用于细胞24 h以及80 mg·L^-1作用于细胞不同时间（0，12，24，48 h），高效液相色谱法测定细胞内总胆固醇（TC），游离胆固醇（FC），胆固醇酯（CE）的含量，油红O染色观察菝葜乙酸乙酯提取物对THP-1源性荷脂细胞中脂滴形成的影响，Western blot印迹法检测细胞内SREBP-1蛋白表达变化。 结果： 菝葜乙酸乙酯提取物明显降低THP-1源性荷脂细胞中脂滴含量，细胞内TC，FC，CE水平呈现一定的剂量和时间依赖性下降趋势，同时 SREBP-1蛋白表达上调。 结论： 菝葜乙酸乙酯提取物能引起THP-1源性荷脂细胞TC，FC，CE含量下降，且这种作用与SREBP-1蛋白表达上调有一定关系。

Effect of Ethyl Acetate Extract from Smilax china on Cholesterol Accumulation and SREBP-1 Expression in THP-1-derived Lipid-loaded Cells

Objective: To observe the effect of ethyl acetate extract from Smilax china on the cholesterol metabolism in monocyte/macrophage cell line(THP-1)-derived lipid-loaded cells,and to investigate the effect of the expression of sterol regulatory element binding protein(SREBP-1) and caveolin-1 in this process. Method: The ethyl acetate extract with different density (0,40,80,160 mg·L^-1) were used to detect the level of total cholesterol(TC), free cholesterol(FC), cholesterol ester(CE) by using high performance liquid phase analytic process and the expression of SREBP-1 by Western blot at different time (0,12,24,48 h) in THP-1 derived lipid-loaded cells. Result: The ethyl acetate extract from S.china had some effects on THP-1-derived lipid-loaded cells, the lipid droplet density decreased in cells and the level of TC, FC, CE was decreased with a dose and time-dependent manner. The expression of SREBP-1 was upregulated. Conclusion: The ethyl acetate extract from S.china can decreased the level of TC, FC, CE in THP-1 derived lipid-loaded cells, and it is contributed to the up-regulation of SREBP-1 expression at some degree.