Yang S, et al. Clinica Chimica Acta. 2020 Feb;501:142-146
Atherosclerosis is a chronic inflammatory disease of the arterial wall that is driven and maintained by the influx, proliferation, and activation of immune cells. Atherosclerosis increases the risk of cardiovascular diseases. An in-depth study of the pathogenesis of atherosclerosis is critical for the treatment of atherosclerotic cardiovascular disease. Cells like endothelial cells, vascular smooth muscle cells, macrophages, and others are involved in the development of atherosclerosis. Macrophage, plays an important role in immune cells and display high heterogeneity through the entire process of atherosclerosis. Macrophage polarization means a diverse expression pattern of genes and proteins. There are more than two macrophage phenotypes in human or mouse plaque. The classically activated macrophages (M1) are the first phenotype characterized as pro-inflammatory. The alternatively activated macrophages (M2) plays a preventive role in the progression of human and mouse atherogenesis. These M2 macrophages are divided into four subtypes: M2a, M2b, M2c, and M2d. Mhem, a novel macrophage phenotype stimulated by intraplaque hemorrhage, shows an anti-atherogenic effect via fewer oxidative injuries in human plaque. Moreover, an increasing number of clinical studies are also focusing on the role of macrophage as a predictor of cardiovascular events.
The discovery of different macrophage phenotypes provides an opportunity to study the relationship between macrophage phenotypes and atherosclerosis. Phenotypes such as M1 and Mox promote the development of lesions by expressing pro-inflammatory factors. Phenotypes such as M2 and Mhem mainly decelerate the development of the disease by exerting anti-inflammatory effects. Enormous effects of macrophages on atherosclerosis are inseparably linked to macrophage polarization and the resulting phenotype. Moreover, the significant impact of macrophages on atherosclerosis depend not only on the function of the different macrophage phenotypes but also on the relative ratio of different phenotypes in the plaque. Research on atherosclerosis therapy indicates that the reduced plaque size and enhanced stability are partly due to modulating macrophage polarization.
Therefore, regulating macrophage polarization and changing the proportion of macrophage phenotypes in plaques is a new therapeutic approach for atherosclerosis. Increasing the number of anti-atherosclerotic phenotype in plaque via. certain methods is a helpful approach. After evaluating a large amount of experimental data. The study provided a new perspective for atherosclerosis therapy by summarizing the relationship between macrophage polarization and atherosclerosis, as well as treatment targeting macrophage polarization. Thus, it was concluded that the regulation of macrophage polarization contributes to the improvement in atherosclerotic plaque.
