Free radicals and antioxidant status in rat liver after dietary exposure of environmental mercury

• Published in: Environmental toxicology and pharmacology 2006-11, Vol.22 (3), p.309-314
• Main Authors: Ji, Xiuling, Wang, Wenhua, Cheng, Jinping, Yuan, Tao, Zhao, Xiaoxiang, Zhuang, Huisheng, Qu, Liya
• Format: Article
• Language: English
• Subjects: Antioxidants; Enviromental mercury exposure; Free radicals; Selenium
• ISSN: 1382-6689; 1872-7077
• DOI: 10.1016/j.etap.2006.05.004

Potential health effect of dietary exposure to environmental mercury was examined in this study. Dietary exposure significantly increased content of reduced glutathione (GSH) and activity of glutathione peroxidase (GSH-Px) in rat liver at 7 or 20 days ( P < 0.05; P < 0.01), but parameters droped to normal levels after 90 days of exposure. The early increases of the two antioxidants were partly associated with the co-accumulated selenium. However, activity of superoxide dismutase (SOD) was observed significantly decreased after 30 and 90 days of exposure ( P < 0.05, P < 0.05). Changes of antioxidants were paralleled by the induction and aggravation of free radicals in rat liver at 30 and 90 days ( P < 0.01, P < 0.01), increased nitric oxide (NO) content at 90 days ( P < 0.01). The excess availability of free radicals and the decreased levels of antioxidants resulted in a significant increase of malonyldialdehyde (MDA) after 90 days of exposure, indicating the aggravation of hepatic oxidative status. A number of biomarkers were required to monitor and minimize the health risk for the local population.