Inflammation and coronary artery disease

Abstract

Several evidences, ranging from in vitro experiments, pathologic analysis and epidemiologic studies, show that atherosclerosis is intrinsically an inflammatory disease. The plasma concentrations of interleukin-6 (IL-6) and its hepatic by-product, C-Reactive Protein (CRP), appear to reflect the intensity of occult plaque inflammation and by inference may determine the vulnerability of plaque rupture. The monocyte chemoattractant protein-1 (MCP-1) plays a crucial role in initiating coronary artery disease by recruiting monocytes/macrophages to the vessel wall. This leads to the formation of atherosclerotic lesions and also increases the vulnerability of the plaque. Indeed, circulating IL-6 and MCP-1 levels are elevated in patients with acute myocardial infarction, and also in patients with unstable angina, but not in those with stable angina. The plasma IL-6 and MCP-1 concentrations are also increased after percutaneous coronary intervention (PCI), and late restenosis is correlated with an increase in IL-6 or MCP-1 concentrations after the procedure. This finding suggests that the expression of IL-6 and MCP-1 may not only be related to the instability of atheromatous plaques, but also to the formation of restenotic lesions after PCI. The development of drugs specifically targeted against IL-6 and MCP-1 may be useful in the prevention of plaque formation, myocardial infarction and restenosis.