Skin damage mechanisms related to airborne particulate matter exposure

MAGNANI, NATALIA; MURESAN, XIMENA; BELMONTE, GIUSSEPPE; CERVELLATI, FRANCO; STICOZZI, CLAUDIA; MIRACCO, CLELIA; MARCHINI, TIMOTEO; EVELSON, PABLO; VALACCHI, GIUSEPPE

TOXICOLOGICAL SCIENCES

OXFORD UNIV PRESS

Lugar: Oxford; Año: 2016 vol. 149 p. 227 - 236

1096-6080

Epidemiological studies suggest a correlation between increased airborne particulate matter (PM) and adverse health effects. Cutaneous tissue is continuously exposed to outdoor stressors. The mechanisms of PM-health effects are believed to involve oxidative stress and inflammation. To evaluate the ability of PM promoting skin tissue damage, we analyzed the effect of Concentrated Ambient particles (CAPs) in a Reconstructed Human Epidermis (RHE) model. RHE tissues were exposed to 25 or 100 µg/mL CAPs for 24 or 48 h. CAPs were characterized by SEM. LDH and IL-1α releases were evaluated by ELISA. Isoprostanes, NFkB and COX2 were assessed through immunofluorescence, 4-HNE levels spectrofotometrically and CYP1A1 expression by Western blot. Tissue structure was analyzed by immunohistochemistry and TEM. Considering the LDH released values, RHE seems to be more susceptible to CAPs-induced toxicity after 48 h exposure. A local reactive O2 species (ROS) production increase could be generated from metals present on the particle, and contribute to lipids oxidation. Furthermore, as a consequence of altered redox status, NFkB nucleus translocation was increase upon CAPs exposure, as well as COX2 and CYP levels, which may be involved in the inflammatory response initiated by PM. CAPs also triggered an apoptotic process in skin. TEM analysis showed that CAPs were able to penetrate skin tissue. These findings contribute to the understanding of the cutaneous pathophysiological mechanisms initiated by CAPs exposure, where oxidative stress and inflammation may play predominant roles. Tissue redox unbalance appears to be an important area of study in skin damage, triggered by PM exposure, in order to clarifying the molecular mechanisms involved.