苦瓜蛋白通过下调miR-23b-3p促进三磷酸腺苷结合盒转运体A1表达

Momordicin promotes adenosine triphosphate binding cassette transporter A1 expression by down-regulating miR-23b-3p

目的前期工作发现苦瓜蛋白（MD28）可上调THP-1源性泡沫细胞三磷酸腺苷结合盒转运体A1（ABCA1）的表达而减少胞内的脂质蓄积,但其机制不清楚。文章拟从转录后水平分析其作用机制。方法首先用miRNA芯片技术分析经MD28干预后,50 mg/L ox-LDL处理48 h的THP-1源性泡沫细胞miRNA谱中下调1.5倍的micro RNA（miRNA）,并与Genecards调控ABCA1基因表达的miRNA比较,找到二者共同miRNA,然后以荧光素酶报告基因系统验证其靶基因关系。qRT-PCR检测ABCA1 m RNA和miR-23b-3p的表达水平,Western blot检测蛋白表达水平,油红O染色测定胞内脂质蓄积。结果 miR-23b-3p是miRNA芯片和Genecards的交集,靶基因验证实验证实ABCA1是miR-23b-3p的靶基因。MD28剂量（0 g/L、0.4 g/L、1.2 g/L、3.6 g/L、5 g/L）和时间（0 h、6 h、12h、24 h、48 h）依赖性地上调ABCA1 m RNA及蛋白的表达水平,以1.2 g/L作用12 h最为显著。ox-LDL上调miR-23b-3p表达且被MD28抑制,MD28能减少胞内脂质蓄积,miR-23b-3p的抑制剂可拮抗MD28对ABCA1表达和胞内脂质蓄积的作用。结论 MD28通过下调miR-23b-3p介导其促进THP-1源性泡沫细胞ABCA1表达、减少胞内脂质蓄积作用。

Aim The previous work showed that momordicin（ MD28） can up-regulate the expression of ATPbinding cassette transporter A1（ ABCA1） in THP-1-derived foam cells and reduce the intracellular lipid accumulation,but its mechanism is unclear. This study is to analyze the mechanism of action from the post-transcriptional level. Methods Mi RNA chip was used to analyze the micro RNA（ miRNA） that were down-regulated by 1. 5-fold in the miRNA of THP-1-derived foam cells treated with 50 mg/L ox-LDL for 48 h after the intervention of MD28 and compared with the genecards miRNA which regulates the ABCA1 gene expression. Of common miRNA,target gene relationship between this miRNA and ABCA1 was verified by the luciferase reporter gene system. qRT-PCR was used to detect ABCA1 m RNA and miR-23 b-3 p expression levels,protein was detected by Western blot,oil red O staining was used to detect intracellular lipid accumulation. Results miR-23 b-3 p was the intersection of miRNA chip and genecards. The target gene validation experiment confirmed that ABCA1 was the target gene of miR-23 b-3 p. MD28 dose-dependently（ 0 g/L,0. 4 g/L,1.2 g/L,3.6 g/L,5 g/L） and time-dependently（ 0 h,6 h,12 h,24 h,48 h） up-regulated ABCA1 expression,the highest expression level of ABCA1 was at 1.2 g/L for 12 h of MD28. ox-LDL up-regulated the expression of miR-23 b-3 p and was inhibited by MD28,while MD28 decreased intracellular lipid accumulation,and the inhibitor of miR-23 b-3 p antagonized the effect of MD28 on ABCA1 expression and intracellular lipid accumulation. Conclusion MD28 can up-regulate the expression of ABCA1 and decrease the intracellular lipid accumulation in THP-1 macrophage-derived foam cells by decreasing the expression of miR-23 b-3 p.