AGEs-RAGE相互作用促进巨噬细胞摄取胆固醇的研究

AGEs-RAGE interaction increases the cholesterol uptake in macrophages

摘要:

目的观察糖基化终末产物(advanced glycation end products, AGEs) 及其受体(receptor of advanced glycation end products, RAGE)对巨噬细胞胆固醇摄取功能的影响。方法 培养THP-1细胞株,用PMA诱导分化使其成为巨噬细胞,以100μg/ml的氧化LDL(oxidized LDL, oxLDL)孵育细胞使其转化为泡沫细胞。分别以浓度为300、600μg/ml的AGEs对细胞进行刺激,应用用浓度为10μg/ml的抗RAGE抗体对细胞进行预处理,采用油红O染色测定细胞内脂质含量,通过RT-PCR及Western印迹法来检测各组巨噬细胞RAGE表达以及与胆固醇摄取相关因子SRA2、CD36表达变化,将干预后的巨噬细胞与荧光标记的oxLDL共同孵育,动态观察巨噬细胞在不同干预条件下胆固醇摄取功能的变化。结果 高浓度AGEs诱导后,巨噬细胞内脂质含量增加,RAGE表达增加,SRA2、CD36表达增加,巨噬细胞胆固醇摄取能力增加。应用抗体阻断RAGE轴后,AGEs引起的改变均有明显恢复。结论 AGEs-RAGE相互作用可以促进巨噬细胞摄取胆固醇,增加细胞内脂质累积,从而易于形成泡沫细胞。

Abstract:

ObjectiveTo investigate the effect of AGEs-RAGE axis on the cholesterol uptake of macrophage. Methods Human THP-1 monocytes were treated with PMA (100ng/ml) for 48h, and then induced with oxLDL (100μg/ml) for differentiating to macrophage foam cells. Cells were pretreated by AGEs (300 or 600μg/ml) for 2h, and pre-stimulated with antibody for RAGE (10μg/ml). The oil red O staining and measurement of cholesterol ester were used for evaluating the accumulation of lipid in macrophages. RT-PCR and Western blotting analysis were used to test the mRNA and protein expression of RAGE, SRA2, CD36. The fluorescence intensity was tested for the ability of cholesterol uptake in macrophages. Results After induction of AGEs (600μg/ml), the content of lipid in macrophage was increased, and the expression of RAGE, SRA2, CD36 were increased. The ability of macrophages for cholesterol uptake was enhanced. For blocking up the AGEs-RAGE axis by antibody to RAGE, all the changes were reversed. Conclusion AGEs-RAGE axis can promote cholesterol uptake in macrophages, which were transformed to foam cell.