Omega-3 fatty acids in atherosclerosis and coronary artery disease

Omega-3 polyunsaturated fatty acids have emerged as possible protective factors associated with a decreased risk for myocardial infarction in populations with a high marine food intake, which may relate to effects on lipid metabolism, thrombosis and inflammation. Omega-3 fatty acids decrease triglyceride levels and also compete as substrates for enzymes involved in the biosynthesis of lipid mediators. The balance between omega-3-derived specialized proresolving mediators and pro-inflammatory lipid mediators from arachidonic acid metabolism can be measured as the resolvin-to-leukotriene ratio, which has been shown to predict subclinical atherosclerosis. The results of experimental, observational and randomized studies of omega-3 fatty acids are somewhat variable and should be interpreted in view of the models used and the populations studied. Lay abstract: Almost 40 years after the discovery of protective effects of fish oils on the heart and vessels, the mechanisms of action of omega-3 fatty acids remain unclear. In addition to effects on blood lipid levels, omega-3 fatty acids can be metabolized into bioactive lipid mediators. It has been proposed that such omega-3-derived bioactive lipids counteract the inflammation and blood clotting induced by lipid mediators from omega-6 fatty acids and that this contributes to the beneficial effects of fish oils.