Lipid Peroxidation and Gene Expression of Antioxidant Enzymes in Response to Polycyclic Musks in Earthworm Eisenia Fetida

Polycyclic musks (PCMs) released into the environment have potential impacts on soil organisms such as earthworms. To better understand the toxicity of PCMs, earthworms were exposed to tonalide (AHTN) and galaxolide (HHCB) spiked filter paper for 48 h and impacts on oxidative stress and gene expression were investigated. Levels of lipid peroxidation significantly (P<0.05) increased in time-dependent manner, suggesting that the reactive oxygen species induced cellular oxidative injury of Eisenia fetida might be one of the main toxic effects of PCMs. Gene expressions of superoxide dismutase (SOD) and catalase (CAT) significantly (P<0.05) up-regulated at low doses of AHTN (0.6 mu g/cm(-2)) and HHCB (0.3 mu g/cm(-2)) throughout the 48 h exposure period, while down-regulated at high doses (6.0 mu g/cm(-2) AHTN and 3.0 mu g/cm(-2) HHCB) after 48 h. These results indicate that excessive PCMs could result in oxidative damage in earthworms. To our knowledge, this study is the first description of PCMs causes toxicity in earthworm using a transcript level approach, which can provide new insights into the toxicological mechanism of AHTN and HHCB.