苦瓜蛋白通过肝X受体α上调三磷酸腺苷结合盒转运体A1表达  

Momordicin up-regulating the expression of adenosine triphosphate binding cassette transporter A1 through liver X receptor alpha

作　　者：马小峰[1,2] 肖文超 刘益州[1] 蒋波 王佐 

机构地区：[1]南华大学附属南华医院 [2]南华大学心血管疾病研究所,湖南衡阳421001

出　　处：《湘南学院学报（医学版）》2017年第4期1-6,共6页Journal of Xiangnan University（Medical Sciences）

基　　金：湖南省卫生计生委科研计划课题(B2016139);湖南省教育厅项目(15C1201)

摘　　要：目的观察苦瓜蛋白对THP-1巨噬细胞源性泡沫细胞三磷酸腺苷结合盒转运体A1(ABCA1)及肝X受体α(LXRα)表达的变化和细胞内胆固醇流出的影响,探讨苦瓜蛋白抗动脉粥样硬化的机制。方法加入50 mg/L的ox-LDL共同孵育细胞24 h,诱导THP-1单核巨噬细胞成泡沫细胞。分别加入0、0.5、1.5、4.5 mg/ml苦瓜蛋白或4.5 mg/ml苦瓜蛋白处理THP-1细胞0、3、6、12、24 h,以检测其浓度效用和时间效用。MTT法检测苦瓜蛋白的细胞毒性,液体闪烁计数法测胆固醇流出。实时荧光定量PCR和Western blot分别检测ABCA1、LXRα的mRNA和蛋白水平,设计合成LXRα-siRNA序列,并转染THP-1细胞,Western blot法评估沉默效果。结果苦瓜蛋白浓度低于4.5 mg/ml对THP-1细胞无毒性,并浓度和时间依赖性地促进胆固醇流出和上调ABCA1及LXRα表达水平,以4.5 mg/ml苦瓜蛋白作用效果最强;使用LXRα-siRNA沉默LXRα后,ABCA1的mRNA和蛋白表达水平均显著下降(P<0.05),胆固醇流出显著减少。结论苦瓜蛋白可通过LXRα途径上调ABCA1的表达促使THP-1巨噬细胞源性泡沫细胞胆固醇流出。Objective To investigate the effects of momordicin on the expression of adenosine triphosphate binding cassette transporter A1（ ABCA1） and hepatic X receptor alpha（ LXRα） and the intracellular cholesterol efflux from THP-1 macrophage-derived foam cells,in order to discuss the anti-atherosclerosis mechanism of momordicin.Methods THP-1 mononuclear macrophages were induced into foam cells by being incubated with 50 mg/L ox-LDL for 24 h. THP-1 cells were treated with 0,0.5,1.5,4.5 mg/ml momordicin or 4. 5 mg/ml momordicin for 0,3,6,12,24 hours respectively,and the effects of concentration and length of time were detected. MTT method was used to detect the toxicity of momordicin on THP-1 cells while liquid scintillation counting was used to test cholesterol efflux.Real-time fluorescence quantitative PCR while Western blot were used to detect the mRNA and protein levels of ABCA1 and LXRα.The LXRα-siRNA sequence was designed and transfected into THP-1 cells.The silencing effect was evaluated by Western blot.Results Momordicin concentration possessed no toxicity on THP-1 cells when it below 4.5 mg/ml and it concentration-and-time-dependently promoted the cholesterol efflux and up-regulated the expression of ABCA1 and LXRα,and the effect of momordicin was strongest at 4. 5 mg/ml; The expression of ABCA1 mRNA and protein was significantly decreased after LXRα was silenced by LXRα-siRNA（ P0.05）,and the cholesterol efflux was significantly reduced. Conclusion Momordicin up-regulates the expression of ABCA1 by LXRα pathway,then the cholesterol efflux from THP-1 macrophage derived foam cells can be promoted.

关 键 词：动脉粥样硬化 泡沫细胞 苦瓜蛋白 肝X受体Α 三磷酸腺苷结合盒转运体A1 

分 类 号：R363[医药卫生—病理学]