Urban air pollution induces redox imbalance and epithelium hyperplasia in mice cornea.

Urban air pollution induces redox imbalance and epithelium hyperplasia in mice cornea. Toxicol Appl Pharmacol. 2019 Oct 16;:114770 Authors: Lasagni Vitar RM, Hvozda Arana AG, Janezic NS, Marchini T, Tau J, Martinefski M, Tesone AI, Racca L, Reides CG, Tripodi V, Evelson PA, Berra A, Llesuy SF, Ferreira SM Abstract The aim of the study was to evaluate the time course of the effects of urban air pollutants on the ocular surface, focusing on the morphological changes, the redox balance, and the inflammatory response of the cornea. 8-week-old mice were exposed to urban or filtered air (UA-group and FA-group, respectively) in exposure chambers for 1, 2, 4, and 12 weeks. After each time, the eyes were enucleated and the corneas were isolated for biochemical analysis. UA-group corneas exhibited a continuous increase in NADPH oxidase-4 levels throughout the exposure time, suggesting an increased production of reactive oxygen species (ROS). After 1 week, an early adaptive response to ROS was observed as an increase in antioxidant enzymes. After 4 weeks, the enzymatic antioxidants were decreased, meanwhile an increase of the glutathione was shown, as a later compensatory antioxidant response. However, redox imbalance took place, evidenced by the increased oxidized proteins, which persisted up to 12 weeks. At this time point, corneal epithelium hyperplasia was also observed. The inflammatory response was modulated by the increase in IL-...
Source: Toxicology and Applied Pharmacology - Category: Toxicology Authors: Tags: Toxicol Appl Pharmacol Source Type: research