Abstract 253: Di-n-butyl Phthalate: An Indoor Pollutant Induces Murine Macrophages Oxidative Stress and Inflammation, a Potential Atheropathogenesis Modulator

Abstract

Di-n-butyl phthalate (DBP) is used in air fresheners. It is a colorless oily compound which also used for manufacturing bendable plastics. DBP can cause low acute or chronic toxicity; however, the effect of DBP on humans in the form of air fresheners is not well studied. The effect of DBP on the human cardiovascular system has not been studied. Macrophages are involved in atherosclerosis progression and development; murine macrophages (RAW 264.7) were used for this study. The macrophages were treated with 10uM, 20uM and 50uM DBP for 6 hours, 12 hours and 24 hours. Genes involved in inflammation and antioxidant activity like TNF-a, MCP-1, VCAM-1, NF-kB, PON1, SOCS were analyzed after treatment. macrophages showed statistically significant increases in TNF-alpha expression (p≤ 0.05) after 24 hour treatment with DBP. The expression of NF-kB showed a significant increase in response to DBP treatment (p≤ 0.05) at 24 hours. MCP-1 and VCAM-1 gene expressions were also upregulated after exposure to DBP. Interestingly, catalase gene expression was upregulated in all treatments after 24 hours of exposure however PON-1 gene expression showed differential upregulation responses. Our data clearly suggest that DBP induces inflammation in macrophages. PON1 and catalase upregulated gene expression indicative of a compensatory response to oxidative stress associated with the treatment. Oxidative stress and inflammation mediated macrophages responses strongly linked to atherosclerosis pathogenesis.