E17241 as a Novel ABCA1 (ATP-Binding Cassette Transporter A1) Upregulator Ameliorates Atherosclerosis in Mice

Abstract

Objective: Reverse cholesterol transport, removing excess cholesterol from peripheral tissues, is an important therapeutic target for atherosclerosis treatment. In this study, we propose a new small molecule, E17241, that may be used to treat atherosclerosis by promoting reverse cholesterol transport via ABCA1 (ATP-binding cassette transporter A1) upregulation. Approach and Results: E17241 (4-(1,3-dithiolan-2-yl)-N-(3-hydroxypyridin-2-yl)benzamide) was first identified as an ABCA1 upregulator using a cell-based reporter assay. E17241 significantly increases the mRNA and protein expression levels of ABCA1 in both hepatic cells and macrophages. It promotes cholesterol efflux to apo AI in macrophage cells, and this effect depends on ABCA1. It also decreases total cholesterol content in Ox-LDL (oxidized low-density lipoprotein) loading macrophage cells. E17241 treatment increases the content of 3 H-labeled cholesterol in the feces of male C57BL/6J mice intraperitoneally injected with 3 H-cholesterol-labeled macrophage J774 cells, indicating that it could promote in vivo macrophage reverse cholesterol transport. Compared with the western diet group (western diet–fed male ApoE −/− mice), the E17241 group (western diet+E17241 treatment) shows decreased plasma cholesterol, liver cholesterol, and triglyceride levels, with increased fecal cholesterol content. Importantly, E17241 reduces atherosclerotic lesion areas in the en face aorta and aortic sinus while increasing ABCA1 protein levels in both liver and macrophages. Human proteome microarray, coimmunoprecipitation, and other assays demonstrate that PKCζ (protein kinase C zeta) is a binding target of E17241, and this small molecule increases ABCA1 expression in macrophages via the PKCζ-NR (nuclear receptor) pathway. Conclusions: E17241 may be developed as a new lead or drug candidate for the treatment of atherosclerosis by upregulating ABCA1.