Figure 1.

Epigenetic changes associated with PM exposure. PM2.5 is small enough to be aspirated into alveoli, to be absorbed either by alveolar macrophage or direct translocation into extracellular matrix and vascular endothelial cells, and to be transported into the systemic circulation. The circulating PM2.5 may induce epigenetic changes and systemic inflammation. PM2.5 exposure decreases DNA methylation of LINE-1, decreases DNMT1 and increased DNMT3B expression. PM10 exposure increases HAT activity and cigarette smoke decreases HDAC2 activity. PM2.5 exposure is associated with miRNA changes related to multiple inflammatory pathways.