茶多酚对大鼠系膜细胞摄取氧化型低密度脂蛋白的影响

目的 :探讨茶多酚抑制大鼠肾小球系膜细胞摄取氧化型低密度脂蛋白 (OX-LDL)的作用。方法 :以OX LDL刺激体外培养的大鼠系膜细胞 ,同时用不同浓度茶多酚干预 ,测系膜细胞内总胆固醇 (TC)含量 ,油红 O染色 ,光镜及电镜观察细胞形态。结果 :OX-LDL刺激下系膜细胞TC含量及油红-O染色阳性细胞比例均较无脂蛋白刺激的照系膜细胞增高 ,电镜下见泡沫细胞。随培养液茶多酚浓度由 40ng·L^-1～40mg·L^-1 递增 ,脂蛋白刺激的系膜细胞TC含量及油红-O染色阳性细胞比例递减 ,呈剂量依赖性关系 ,系膜细胞内脂滴数量减少。结论 :40ng·L^-1～40mg·L^-1 茶多酚可呈剂量依赖性抑制大鼠系膜细胞摄取OX-LDL。

The Inhibitive Effect of Tea Polyphenols on Oxidized Low Density Lipoprotein Intake in Cultured Rat Mesangial Cells

Objective: To study the inhibitive effect of tea polyphenols (TP) on oxidized low density lipoprotein (OX LDL) intake in cultured rat mesangial cells. Method: Rat mesangial cells incubated in 80 mg·L^-1 OX LDL were treated with TP at different concentrations. Total cholesterol (TC) content of the mesangial cells and proportion of mesangial cells containing lipid droplets were measured, and ultrastructure observation was performed. Result: Foam cells were observed in mesangial cells stimulated by OX LDL, and both the TC content and the proportion of lipid droplet containing cell were higher in these cells than in mesangial cells cultured in lipid free conditions. There were concentration dependent decreases both in TC content and lipid droplet containing cell proportions when treated with TP from 40 ng·L^-1 to 40 mg·L^-1 . The number of lipid droplets was also decreased in TP treated mesangial cells. Conclusion: TP has an inhibitive effect on OX LDL intake in cultured rat mesangial cells, which is in a concentration dependent manner from 40 ng·L^-1 to 40 mg·L^-1 .