Excess free cholesterol that accumulates along the walls of blood vessels is transported to the liver for excretion via a process known as reverse cholesterol transport.
Three proteins, known as ABCA1, SR-BI, and ABCG1, have been shown to promote cholesterol efflux and protect against atherosclerosis in mice, but their roles in mediating reverse cholesterol transport from macrophages remains unclear.
In a study appearing online on July 26 in advance of publication in the August print issue of the Journal of Clinical Investigation, Daniel Rader and colleagues from the University of Pennsylvania studied macrophage reverse cholesterol transport in mice and found that ABCA1 and ABCG1, but not SR-BI, promote reverse cholesterol transport in macrophages and that ABCA1 and ABCG1 have additive effects on this process.
The data suggest that ABCA1 and ABCG1 cooperatively contribute to macrophage reverse cholesterol transport and that therapeutic intervention to increase macrophage ABCA1 and ABCG1 expression may be an effective strategy to inhibit the development of, or reduce, atherosclerosis.
TITLE: Macrophage ABCA1 and ABCG1, but not SR-BI, promote macrophage reverse cholesterol transport in vivo