Résumé
Epidemiological results show that airborne particulate matter (PM) induces health alterations in line with pulmonary and cardiovascular pathologies. Deleterious effects of PM on the skin have also been investigated. A possible approach to prevent Reactive Oxygen Species (ROS)-mediated disorders for both preventive and treatment means is based on the use of substances, which can be found in plants. These can act as secondary metabolites, and lignans are a promising candidate. Thus, the objective of this study was firstly to identify reconstructed human epidermis, using a transcriptomic approach, and also to identify the effects of Urban Dust and of Urban Dust and Schisandra chinensis (S.C.) extract on the expression of genes that are involved in the response to cellular protection mechanisms. Secondly, we examined the effect of an active extract from S.C. on the protection of human keratinocytes damages that were caused by pollution, through the evaluation of Nrf2 and AhR pathways, NF-kB, and DJ-1. Urban Dust included the over-expression of metalloproteinases MMP-1 and MMP-9 and an increase in Glutathione peroxidase 2 (GPX2). In the presence of Urban Dust, S.C. extract activated the over-expression of several genes that are involved in the antioxidant response and in the detoxification pathway, including Ferritin light chain (FTL) and GPX2. Exposure to urban dust activated the cytoplasmic expression of NF-kB and AhR, when compared to the control. Co-treatment of Urban Dust and S.C. extract increased DJ-1 protein levels, Nrf2 expression, and decreased AhR and NF-kB in the cytoplasm. At the same time, this co-treatment increased SOD2 expression (50%: p < 0.001) and catalase activity (120%: p < 0.05), when compared to Urban Dust alone. Thus, S.C. might be able to protect the Normal Human Epidermal Keratinocytes (NHEK) from environmental aggression, by fighting the harmful effects of urban pollution.