Abstract: OBJECTIVE:To examine the antioxidative and hepatoprotective activities of the effective fraction separated from the fruit of Livistona chinensis(FLC)and to explore the possible mechanism.METHODS:The antioxidative activities of the various fractions separated from FLC were analyzed by in vitro DPPH(1,1-diphenyl-2-picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl,DPPH) radical and superoxide anion free radical(O~(2-)) scavenging assays.The potential hepatoprotective effects of the ethyl acetate fraction separated from FLC(EFLC) were examined in LO_2 cells and mice.LO_2 cells were incubated with EFLC and exposed to H_2O_2-induced oxidative stress.BABL/C mice were orally administered EFLC for consecutive7 d,and fulminant hepatitis was induced by cauda vein injection of Con A on day 7.RESULTS:EFLC showed prominent antioxidative effects in DPPH-and O~(2-) scavenging assays.EFLC pretreatment effectively protected LO_2 cells from H_2O_2-induced oxidative stress by decreasing apoptosis and raising the levels of antioxidant enzymes.Additionally,EFLC protected mice against Con A-induced fulminant hepatitis by markedly reducing the serum levels of alanine transaminase and aspartate aminotransferase,attenuating histological damage of the mouse liver,and elevating the levels of glutathione peroxidase and total superoxide dismutase,while decreasing the contents of methane dicarboxylic aldehyde,tumor necrosis factor-α,and interleukin-1β in the mouse liver.Furthermore,EFLC pretreatment downregulated the protein expression of B-cell lymphoma 2(Bcl-2) associated X protein,caspase-3,caspase-8,Fas,and Fas L,while upregulating the protein expression of Bcl-2 in the mouse liver.CONCLUSION:These findings revealed that EFLC effectively protected against in vivo and in vitro liver injury,and the mechanism is closely associated with its antioxidative and anti-apoptotic properties.

Key words: Hepatitis,Toxins, Antioxidants, Livistona chinensis, Hepatoprotection