人膜转运蛋白ABCA1表达上调剂的筛选与鉴定

Screening and identification of the upregulators of ATP-binding cassette transporter A1

人ATP结合盒转运体A1(ATP-binding cassette transporter A1,ABCA1)可介导细胞内磷脂和游离胆固醇转运至贫脂或无脂的载脂蛋白A-I(apolipoprotein A-I,apoA-I),从而促进高密度脂蛋白(high density lipoprotein,HDL)生成,启动胆固醇逆转运过程,在机体清除多余脂质的过程中发挥重要作用。因此,本研究以ABCA1为靶点,前期建立了ABCA1上调剂抗动脉粥样硬化(atherosclerosis,AS)药物筛选模型,以期寻找具有新作用机制的抗AS药物。在此研究中,利用该模型对1 600个化合物进行筛选,发现2030421B上调活性大于50%,其EC50为0.50μg.mL-1。进一步研究发现,2030421B不仅能上调ABCA1的mRNA以及蛋白水平,而且能使小鼠巨噬细胞RAW264.7内胆固醇流出增加,脂滴量减少,是具有较好效果的ABCA1上调剂。

ATP-binding cassette transporter A1 （ABCA1） promotes cholesterol and phospholipid efflux from cells to lipid-poor apolipoprotein A-I （apoA-I）, and plays a key role in the initial steps of the whole process of reverse cholesterol transport （RCT）. Upregulation of ABCA1 is beneficial for atherosclerosis （AS） prevention and/or therapy, which indicated that ABCA1 was a target for anti-AS drug development. In the previous study, a high-throughput screening method was established using ABCAlp-LUC HepG2 cell line to find the upregulators of ABCA1. In the present study, compound 2030421B was found using this method, with ECs0 of 0.50 tg.mL-1. The compound was further identified as an upregulator of ABCA1 expression by real-time quantitative reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting analysis. Studies also showed that the 2030421B could induce apoA-I-mediated cholesterol efflux and inhibit lipids uptake into mouse peritoneal macrophages RAW264.7.