DNA methylation changes in A549 cells after four weeks of exposure to 30 μg/ml diesel exhaust particles.

Diesel exhaust particles (DEP), which contain hazardous compounds, are emitted during the combustion of diesel. As approximately one-third of the vehicles worldwide use diesel, there are growing concerns on the risks posed by DEP to human health. Long-term exposure to DEP is associated with airway hyperresponsiveness, pulmonary fibrosis, and inflammation; however, the molecular mechanisms behind the effects of DEP on the respiratory tract are poorly understood. Such mechanisms can be addressed by examining transcriptional and DNA methylation changes. In this study, we investigated the effect of 4 weeks exposure to 30 μg/ml DEP on DNA methylation levels in A549 cells. A549 cells were treated with 30 μg/ml DEP for four weeks, using four biological replicates. The DNA methylation levels of 850K CpG sites were obtained for control and treated groups using the IInfinium MethylationEPIC BeadChips microarray. The effect of DEP on DNA methylame was assesed based on the results of differentially methylated analyses compared to the control