Antioxidant Responses in the Cytotoxicity of Isolated Rainbow Trout (Oncorhyncus Mykiss) Hepatocytes Induced by Di(2-Ethylhexyl) Phthalate

Abstract

Di(2-ethylhexyl) phthalate (DEHP) is a plasticizer that is widely used. In the present study, the primary cultured hepatocytes of rainbow trout (Oncorhyncus mykiss) were exposed to DEHP (0, 25, 50, 100, and 200 1.1M) for 24 h and the cytotoxic effects were investigated using the lactate dehydrogenase (LDH) release and antioxidant defense system biomarkers. According to the results, DEHP caused significant LDH releases at concentrations of 50, 100, and 200 mu M. The superoxide dismutase (SOD) activity increased significantly with 25 mu M DEHP, whereas its activity was significantly decreased with 100 mu M DEHP. The catalase (CAT) activity significantly increased with all of the DEHP concentrations, while a simultaneous decrease in CAT activity with SOD activity was observed with 100 mu M DEHP. The glutathione peroxidase activity increased with all of the DEHP concentrations. The glutathione-S-transferase activity remained unchanged with 25, 50, and 100 mu M DEHP, but increased significantly with 200 mu M DEHP. Levels of reduced glutathione elevated with 50 and 200 mu M DEHP. The results suggested that DEHP cytotoxicity is involved in antioxidant responses in hepatocytes. The study will offer insight into the mechanism of DEHP-induced cytotoxicity.