Prolonged systemic inflammation and damage to the vascular endothelium following intratracheal instillation of air pollution nanoparticles in rats

BACKGROUND: Exposure to air pollution is associated with cardiovascular disease, including increased morbidity and mortality rates. OBJECTIVE: The aim of this investigation was to assess the effect, in rats, of intratracheal instillation of particulate air pollution on biomarkers of leucocyte activation and vascular endothelial damage. METHODS: Air pollution particles (PM10) were instilled into rats, and blood samples were taken three days and six weeks post instillation. Plasma neutrophil elastase and Von Willebrand factor were measured by ELISA. RESULTS: Plasma neutrophil elastase increased from 175 +/- 44 ng/ml at baseline to 288 +/- 26 ng/ml 3 days post instillation (p = 0.038). vWF increased from 0.160 +/- 0.015 IU/ml at baseline to 0.224 +/- 0.015 IU/ml at 3 days post and 0.208 +/- 0.01 IU/ml at 6 weeks post (p = 0.006, ANOVA). sICAM-1 increased from 17.75 +/- 0.70 ng/ml at baseline to 19.03 +/- 0.33 ng/ml at 3 days post and 21.72 +/- 1.16 ng/ml at 6 weeks post (p = 0.009, ANOVA). CONCLUSION: Instillation caused prolonged systemic inflammation, activation of blood leucocytes and damage to the vascular endothelium.