Variation in biological effects of exposure to different nanoparticles.
Gwinn-MR; Leonard-SS; Vallyathan-V
Toxicologist 2006 Mar; 90(1):112
Human exposure to nanoparticles, whether deliberate (gene therapy) or incidental (occupational) has not yet been well-studied. Studies have shown that increased exposure to fine particulate ambient air pollution has a direct association to increased morbidity and mortality in the general population. There are two main characteristics of nanoparticles that make them attractive to a variety of industries: their small size yet increased surface area, and their ability to increase material strength yet remain lightweight. These characteristics combined with chemical make-up may lead to inflammation, cell injury and disease development. This study was designed to test the biological response to four different nanoparticles of comparable size diameters to determine the effect of particle chemical make-up on exposure to normal human bronchial epithelial cells (HBEAS). Analysis was performed to determine differences in reactive oxygen species (ROS) production, apoptosis, and cell cycle analysis. Changes in ROS production were seen between all four nanoparticles analyzed, with the most production related to exposure to CuO, a transitional metal (CuO > CeO2 > SiO2 > TiO2). Gene expression analysis showed similar patterns of expression for the four nanoparticles analyzed with genes related to antigen processing, DNA damage repair, nucleotide binding and transport. However, TiO2 showed a different pattern of expression as compared to control and the other nanoparticles in cell cycle control genes. This difference in cell cycle control genes was not reflected in cell cycle analysis at time points analyzed and longer time points are under investigation. These results suggest that the chemical make-up of the nanoparticles is important in relation to ROS generation and changes in DNA damage and cancer gene expression.
Biological-effects; Mortality-data; Mortality-rates; Morbidity-rates; Airborne-particles; Air-contamination; Exposure-levels; Exposure-assessment; DNA-damage; Genes; Nanotechnology
Research Tools and Approaches: Cancer Research Methods
The Toxicologist. Society of Toxicology 45th Annual Meeting and ToxExpo, March 5-9, 2006, San Diego, California