Epigenetic marks after human respiratory epithelium exposure to volatile organic compounds mixtures

Abstract : Chronic exposures to air pollutants are associated with the development or exacerbation of respiratory and allergic diseases, such as asthma, the onset of which could be explained by the emergence of epigenetic events during life. Among these pollutants, Volatile Organic Compounds (VOCs) are a ubiquitous chemical family in indoor air and constitute an important part of the human exposures, and therefore of the human exposome. The aim of this study was to evaluate the epigenetic responses of human bronchial epithelium after repeated exposures to a mixture of VOCs enriched with Formaldehyde (FA) and Hexanal (HEX). Our results indicated a dose- and time-dependent modulation of gene expressions for epigenetic, but also inflammatory and antioxidant mechanisms. An up-regulation of epigenetic gene expression was observed after exposure to VOCs mixture enriched with FA, while conversely a down-regulation was noted after exposure to VOCs mixture enriched with HEX.