The critical role of endothelial function in fine particulate matter-induced atherosclerosis.

Ambient and indoor air pollution contributes annually to approximately seven million premature deaths. Air pollution is a complex mixture of gaseous and particulate materials. In particular, fine particulate matter (PM) plays a major mortality risk factor particularly on cardiovascular diseases through mechanisms of atherosclerosis, thrombosis and inflammation. A review on the PM-induced atherosclerosis is needed to better understand the involved mechanisms. In this review, we summarized epidemiology and animal studies of PM-induced atherosclerosis. Vascular endothelial injury is a critical early predictor of atherosclerosis. The evidence of mechanisms of PM-induced atherosclerosis supports effects on vascular function. Thus, we summarized the main mechanisms of PM-triggered vascular endothelial injury, which mainly involved three aspects, including vascular endothelial permeability, vasomotor function and vascular reparative capacity. Then we reviewed the relationship between PM-induced endothelial injury and atherosclerosis. PM-induced endothelial injury associated with inflammation, pro-coagulation and lipid deposition. Although the evidence of PM-induced atherosclerosis is undergoing continual refinement, the mechanisms of PM-triggered atherosclerosis are still limited, especially indoor PM. Subsequent efforts of researchers are needed to improve the understanding of PM and atherosclerosis. Preventing or avoiding PM-induced endothelial damage may greatly reduce the occurrence and development of atherosclerosis.