Skin biological responses to urban pollution in an ex vivo model

International audienceThe skin epidermis is continuously exposed to external aggressions, including environmental pollution. The cosmetic industry must be able to offer dedicated products to fight the effectsof pollutants on the skin. We set up an experimental model that exposed skin explantsmaintained in culture to a pollutant mixture. This mixture representing urban pollution wasdesigned on the basis of the French organization ‘Air Parif’ database. A chamber, calledPollubox®, was built to allow a controlled nebulization of P on the cultured human skinexplants. We investigated ultrastructural morphology by transmission electron microscopy ofhigh pressure frozen skin explants. A global transcriptomic analysis indicated that the pollutant mixture was able toinduce relevant xenobiotic and antioxidant responses. Modulated detoxifying genes werefurther investigated by laser micro-dissection coupled to qPCR, and immunochemistry. Bothapproaches showed that P exposure correlated with overexpression of detoxifying genes andprovoked skin physiological alterations down to the stratum basale. The model developedherein might be an efficient tool to study the effects of pollutants on skin as well as apowerful testing method to evaluate the efficacy of cosmetic products against pollution