Effects of Subway Particulate Matter Component on Vascular Endothelial Cells

抄録

Cardiovascular diseases are the leading cause of global mortality; with endothelial dysfunction as the initiating stage and air pollution as a substantial environmental risk factor. Several lines of evidence have linked air pollution to cardiovascular morbidity and mortality. However, there is dearth of evidence on the health effects of air quality in enclosed subways with high metal composition due to wear of rail and brake. Therefore, the aim of this study was to investigate the effects of iron oxide particles on the health and physiological function of the vascular endothelium. Human Umbilical Vein Endothelial cells (HUVECs) were cultured as monolayers before exposure to 0, 25, 75 and 200 μg/mL of iron oxide particles for 6, 24 and 48 h. Cell viability, Lactate dehydrogenase (LDH) release, reactive oxygen species (ROS), Interleukins 6 and 8 (IL-6 and IL-8), Endothelin 1 (ET-1) and Plasminogen Activator Inhibitor 1 (PAI-1) production were assayed. Iron oxide caused significant dose-dependent loss in HUVECs’ cell viability with corresponding substantial increased LDH release. In addition, increased production of ROS and pro-inflammatory cytokines such as IL-6 and IL-8 were observed. Furthermore, production of PAI-1, a fibrinolytic modulator and ET-1, a vasoconstrictor significantly decreased compared to control with accompanying cell death and loss of membrane integrity. Overall, these results suggest that iron oxide-rich subway particulate matter can significantly impair endothelial function and cause coagulation dysfunction especially through gross cellular damage.