Humans with atherosclerosis have impaired ABCA1 cholesterol efflux and enhanced high-density lipoprotein oxidation by myeloperoxidase.

Rationale: The efflux capacity of high-density lipoprotein (HDL) with cultured macrophages associates strongly and negatively with coronary artery disease status, indicating that impaired sterol efflux capacity might be a marker-and perhaps mediator-of atherosclerotic burden. However, the mechanisms that contribute to impaired sterol efflux capacity remain poorly understood.

Objective: Our aim was to determine the relationship between myeloperoxidase-mediated oxidative damage to apolipoprotein A-I, the major HDL protein, and the ability of HDL to remove cellular cholesterol by the ATP-binding cassette transporter A1 (ABCA1) pathway.