Identification of two antagonists of the scavenger receptor CD36 using a high-throughput screening model.
CD36, a class B scavenger receptor, is an integral membrane protein that mediates the endocytosis of modified lipoproteins. The functions of CD36 are complex and have been associated with atherosclerosis. In the current study, we developed a high-throughput screening (HTS) assay to identify small molecule antagonists by expressing human CD36 using a Bac-to-Bac baculovirus expression system in Spodoptera frugiperda (Sf9) cells. Uptake of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate-labeled acetylated low-density lipoprotein (DiI-AcLDL) revealed that the IC(50) values for the CD36 ligands oxidatively modified LDL (Ox-LDL), Ac-LDL, and high-density lipoprotein (HDL) were 0.039, 0.019, and 0.010 microg/ml, respectively. Using the HTS assay, two novel compounds, 2016481B and 2038751B, were found to inhibit DiI-AcLDL uptake in insect cells and exhibited IC(50) values of 17.4 and 23.7 microM, respectively. These two novel compounds also inhibited DiI-AcLDL uptake in cultured Chinese hamster ovary (CHO) cells permanently expressing human CD36. Furthermore, these two compounds inhibited lipid accumulation in RAW 264.7 murine macrophage cells in foam cell assays. This HTS assay represents a potential method for identifying more effective macrophage scavenger receptor antagonists, which may serve as starting points for the development of novel anti-atherosclerotic agents.
Xu
Yanni
Y
Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
Wang
Juan
J
Bao
Yi
Y
Jiang
Wei
W
Zuo
Lian
L
Song
Danqing
D
Hong
Bin
B
Si
Shuyi
S
D000818:Animals; D016367:Baculoviridae; D001599:Berberine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D018955:CD36 Antigens / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D015870:Gene Expression; D057166:High-Throughput Screening Assays / Q000379:methods*; D006801:Humans; D007211:Indoles / Q000737:chemistry* / Q000494:pharmacology; D008024:Ligands; D008075:Lipoproteins, HDL / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000378:metabolism; D051379:Mice; D008956:Models, Chemical; D011994:Recombinant Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D018411:Spodoptera / Q000235:genetics / Q000378:metabolism
C550230:2016481B compound; C550229:2038751B compound; D018955:CD36 Antigens; D007211:Indoles; D008024:Ligands; D008075:Lipoproteins, HDL; D008077:Lipoproteins, LDL; D011994:Recombinant Proteins; C032629:acetyl-LDL; C099252:oxidized low density lipoprotein; D001599:Berberine