Hepatoprotective Activity of Fresh Polygonum Multiflorum Against HEP G2 Hepatocarcinoma Cell Proliferation

The modulatory activity of water extracts from fresh roots of Polygonum multiflorum (WRP) on oxidative stress in two liver cell lines was investigated for the first time. WRP increased antioxidant enzyme activities in Clone 9 cells, including catalase (CAT), glutathione-S-transferase (GST), glutathione reductase (OR), and glutathione peroxidase (GPx). The intracellular glutathione (GSH) level was also increased in the Clone 9 cells owing to antioxidase activity elevating effect by WRP treatment for 24 h. On the other hand, reactive oxygen species (ROS) were generated in abundance upon WRP treatment in Hep G2 cells, resulting in the suppression of cell proliferation. Apoptosis was increased to 78% and 77% after WRP (1000 mu g/mL) treatment for 24 and 48 h, respectively. Moreover, WRP stimulated the activation of caspase-8, caspase-9, and ultimately caspase-3. Hep 02 cell growth suppression and caspase induction by WRP were greater than that by emodin-like substances (WRPE), a major active compound. These results indicated that phytochemicals present in extracts of P. multiflorum root act synergistically to promote apoptosis, suggesting the possible use of these extracts for hepatoprotection.