Toona sinensis Roem leaf extracts improve antioxidant activity in the liver of rats under oxidative stress.

Abstract Toona sinensis Roem (TS) is an herbal plant widely cultivated in Asia. Recently, several antioxidant compounds in TS leaf (TSL) extracts were chemically identified including quercetin, gallic acid, and others. However, in vivo experiments regarding the antioxidative function of TSL are limited. In this study, Sprague Dawley (SD) rats with oxidative stress were successfully established by intraperitoneal injection of hydrogen peroxide (H 2 O 2 ) (1 mmol/kg BW) and fed with different TSL extracts for in vivo antioxidation evaluation. Among the TSLs tested in this study, TSL6 exhibited the best antioxidative effects which increased the enzyme activities of catalase, cupper/zinc superoxide dismutase (Cu/Zn SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and Glutathione S transferase (GST) activities in liver compared to those in TSL-2 and TSL-2P groups. In conclusion, we provide the strong in vivo evidences for the first time that TSL extracts ameliorate the antioxidant enzymes (AOEs) activity in liver and is beneficial for the hepatic detoxification.