Newborn histone modifications and gestational exposure to particulate matter air pollution

Abstract

OPS 48: Air pollution and epigenetics, Room 417, Floor 4, August 26, 2019, 4:30 PM - 5:30 PM Background: Exposure to particulate air pollution has been linked with risk of disease in later life. Changes in DNA histone modifications might have long-term adverse health effects. We aimed to investigate the association between prenatal exposure to air pollution and levels of total histone H3 and specific trimethylation marks in cord blood. Methods: We measured cord plasma total histone H3, H3k4me3 and H3K36me3 in 614 samples from the ENVironmental Influence ON early AGEing (ENVIRONAGE) birth cohort. We used a high-resolution air pollution model to estimate exposure to particulate matter with a diameter less than 2·5 μm (PM2·5) and black carbon (BC), and NO2 over the different trimesters of pregnancy and the entire pregnancy on the basis of maternal address. The association between prenatal air pollution exposure and specific methylation marks was analysed with a linear regression model, while accounting for covariates and potential confounders. Findings: PM2.5 exposure averaged (SD) 13.4 µg/m3 (2.6) for the duration of pregnancy, black carbon exposure 1.29 µg/m3 (0.31) and NO2 exposure 17.98 µg/m3 (4.57). H3K4me3 was positively associated with gestational PM2.5 exposure, a 24.1% (p=0.0007) was observed for each 5 µg/m3 increase in PM2.5 exposure. Cord blood H3K36me3 levels were inversely associated with entire pregnancy exposure with an 18.3% (p= 0.03) decrease in association with a 5 µg/m3 increment in PM2.5 exposure. For the entire pregnancy a 14.7% (p<0.001) increase in total histone H3 levels was associated with a 5 µg/m3 increment in exposure. Results for other exposures were similar. In conclusion, exposure to particulate air pollution during pregnancy is significantly associated with levels of cord plasma histone H3 modifications at birth. Particulate air pollution induced changes in cord plasma histone H3 modifications during early life and might be a risk factor in the development of air-pollution related disease, later in life.