Abstract
Because vascular endothelial cell inflammation is critical in the development of cardiovascular pathology, we hypothesized that direct exposure of human aortic endothelial cells (HAECs) to ultrafine particles induces an inflammatory response. To test the hypothesis, we incubated HAECs for 4 h with different concentrations (0.001–50 μg/ml) of CeO2 nanoparticles and subsequently measured mRNA levels of the three inflammatory markers intercellular adhesion molecule 1 (ICAM-1), interleukin (IL)-8, and monocyte chemotactic protein (MCP-1) using real-time polymerase chain reaction (PCR). Ceria nanoparticles caused very little inflammatory response in HAECs, even at the highest dose. This material is apparently rather benign in comparison with Y2O3 and ZnO nanoparticles that we have studied previously. These results suggest that inflammation in HAECs following acute exposure to metal oxide nanoparticles depends strongly on particle composition.
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Acknowledgments
The authors thank Alexandra Navrotsky, John Neil, and Weiqun Chen for use of XRD and BET instruments and related technical assistance.
Declaration of interest: This work was supported in part by grants from the Superfund Basic Research Program with grant no. 5P42ES04699 from the National Institute of Environmental Health Sciences, National Institutes of Health, P30-ES05705 from NIEHS, and HL55667 from NHLBI. Research described in this article was also conducted under contract to the Health Effects Institute (HEI), an organization jointly funded by the U.S. Environmental Protection Agency (EPA) (Assistance Agreement R82811201) and automotive manufacturers. The contents of this article do not necessarily reflect the views of HEI; nor do they necessarily reflect the views and policies of the U.S. EPA or of motor vehicle and engine manufacturers. Although the research described in the article has been funded in part by the U.S. Environmental Protection Agency through grant RD-83241401-0 to the University of California, Davis, it has not been subject to the agency's required peer and policy review and therefore does not necessarily reflect the views of the agency and no official endorsement should be inferred.