Ethyl acetate extract of Wedelia chinensis inhibits tert-butyl hydroperoxide-induced damage in PC12 cells and D-galactose-induced neuronal cell loss in mice

BACKGROUND Wedelia chinensis is traditionally used as a hepatoprotective herb in Taiwan. The aim of this study was to evaluate the neuroprotective potential of W. chinensis. METHODS An ethyl acetate extract of W. chinensis (EAW) was prepared and analyzed by HPLC. The neuroprotective potential of EAW was assessed by tert-butylhydroperoxide (t-BHP)-induced damage in PC12 cells and D-galactose-induced damage in mouse cortex. RESULTS EAW exhibited potent radical scavenging property and highly contained luteolin and wedelolactone. EAW decreased t-BHP-induced reactive oxygen species (ROS) accumulation, cytotoxicity and apoptosis in PC12 cells. EAW and its major constituents blocked t-BHP-induced cytochrome C release and Bcl-2 family protein ratio change. EAW and its major constituents increased the endogenous antioxidant capacity evaluated by the binding activity assay of nuclear factor E2-related factor 2 (Nrf2) to antioxidant response element (ARE) and nuclear translocation of Nrf2 respectively in PC12 cells. Finally, EAW inhibited D-galactose-induced lipid peroxidation, apoptosis and neuron loss in the cerebral cortex of mice. CONCLUSION These results demonstrate that W. chinensis has neuroprotective potential through blocking oxidative stress-induced damage and that luteolin and wedelolactone contribute to the protective action.