红花黄素A对ABCA1介导的THP-1源性泡沫细胞胆固醇流出的影响

Effect of hydroxysafflor yellow A on ABCA1- mediated cholesterol efflux in THP- 1 macrophage- derived foam cells

目的探讨红花黄素A(HSYA)对THP-1源性泡沫细胞载脂蛋白AI(Apo AI)介导的胆固醇流出和三磷酸腺苷结合盒转运体A1(ABCA1)表达的影响及其机制。方法 160 nmol/L PMA孵育THP-1巨噬细胞24h后,诱导分化成巨噬细胞后在50 mg/L氧化低密度脂蛋白培养48 h,使巨噬细胞转化为泡沫细胞。以HSYA 2mmol/L或HSYA 2 mmol/L+ABCA1 siRNA作用不同时间(0、12、24、48 h)或不同浓度(0、1、2、4 mmol/L)HSYA或HSYA+ABCA1 siRNA作用24 h,采用液体闪烁计数法观察Apo AI介导细胞内胆固醇的流出,Western blot检测细胞ABCA1的蛋白表达,定量PCR检测细胞ABCA1的mRNA表达。结果 HSYA呈浓度依赖性和时间依赖性增加胆固醇的流出(P<0.05),ABCA1 siRNA与HSYA共处理细胞后明显抑制HSYA促胆固醇流出作用(P<0.01)。HSYA上调泡沫细胞ABCA1蛋白和mRNA的表达(均P<0.05)。结论 HYSA通过促进泡沫细胞ABCA1表达增加Apo AI介导的胆固醇流出。

Objective To investigate the effects of hydroxysafflor yellow A（ HSYA） on apolipoprotein AI（ Apo AI） mediated cholesterol efflux and ATP- binding cassette transporter A1（ ABCA1） expression and related mechanism in THP- 1 macrophage- derived foam cells. Methods The human THP- 1 macrophages were incubated in phorbol- 12- myristate acetate（ PMA,160 nmol / L） for 24 h and then in 50 mg / L oxidized low density lipoprotein（ ox-LDL） for 48 h for induced transformation to foam cells. Foam cells were treated for different lengths of time（ 0,12,24,48 h） with 2 mmol / L HSYA,or with different doses of HSYA（ 0,1,2,4 mmol / L） for 48 h,or with HSYA ＋ ABCA1 siRNA for 24 h. Cholesterol efflux was detected by liquid scintillation counting. The protein- level and mRNA- level expressions of ABCA1 were detected by Western blot and RT- PCR,respectively. Results HSYA increased Apo AI mediated cholesterol efflux in a time- and dose- dependent manner（ P〈0. 05）. However,the action of HSYA facilitating cholesterol efflux was inhibited in THP- 1 derived macrophage coincubated with ABCA1 siRNA（ P〈0. 01）. In addition,HSYA significantly up- regulated the expression of ABCA1 at protein and mRNA levels（ P〈0. 05）. Conclusion HSYA increases Apo AI mediated cholesterol efflux in THP- 1 macrophage- derived foam cells by enhancing ABCA1 expression.