Coronary atherosclerosis and oxidative stress as reflected by autoantibodies against oxidized low-density lipoprotein and oxysterols

Clinical studies and animal experiments have demonstrated that oxidized low-density lipoprotein (oxLDL) and oxysterols play important roles in atherogenesis. OxLDL is immunogenic, and autoantibodies (Ab) against oxLDL are detectable in serum. We investigated the relevance of oxysterols and Ab against-oxLDL to coronary artery disease (CAD) in 183 patients undergoing coronary angiography. Patient groups included angiographically normal subjects (<75% stenosis), others with spasm (>75% narrowing in response to acetylcholine), and some others with fixed stenosis (>75%). The group with stenosis was subdivided into patients with stable and unstable angina. Serum concentrations of autoantibodies and 25-, 27-, and 7-β-hydroxycholesterols were significantly higher in the stenotic group than in the normal group (P<0.01, P<0.05, P<0.05, and P<0.05, respectively). Antibodies, but not oxysterol concentrations, were significantly greater in subjects with unstable than with stable angina (P<0.01). We conclude that anti-oxLDL antibody and oxysterol concentrations are associated with coronary artery stenosis, and that oxidative stress may be greatly increased in unstable angina.