Nasal cytology and genotoxic damage in nasal epithelium and leukocytes: asthmatics versus nonasthmatics.

ABSTRACT

BACKGROUND: The best example of a chronic inflammatory respiratory disease is asthma, a disease which has an increasing prevalence worldwide. This chronic inflammation is also related to the generation of oxidative stress since the cells involved in the allergic reaction are capable of producing reactive oxygen species (ROS), and this might predispose asthmatics to increased genotoxic damage. METHODS: A respiratory symptomatology questionnaire was self-applied by asthmatic and nonasthmatic students. A single cell gel electrophoresis assay in two different cell types (nasal epithelial cells and leukocytes) was performed, and the cytology of the nasal smears stained with HE was evaluated. RESULTS: Both groups reported having a runny nose. Asthmatics had greater DNA damage in the nasal epithelial cells in contrast to nonasthmatics. In leukocytes no statistical significance in DNA damage was identified. Metaplasia was evident in asthmatics that also showed eosinophils and neutrophils as well as goblet cells and mucus at a higher frequency compared with nonasthmatics. CONCLUSIONS: Nasal symptoms did not correlate with genotoxic damage, since they were reported in both groups. Nasal epithelial cells of asthmatics are more sensitive to genotoxic damage, and chronic inflammatory response. Also the activity of eosinophils might mediate the DNA damage through the generation of ROS.