ANTIOXIDANT EFFECT OF CRUDE WATER EXTRACT OF VETIVERIA ZIZANIOIDES (GRAMINEAE) IN MICE WITH ACETAMINOPHEN INDUCED HEPATOTOXICITY
Acetaminophen (APAP) is widely used as an analgesic and antipyretic drug. Large dose of APAP results in severe hepatic necrosis due to the oxidative stress. This work evaluates the antioxidant activity of crude water extract of Vetiveria zizanioides rootsagainst a single dose of APAP induced acute hepatotoxicity. Mice were treated with 300 mg/kg of APAP dissolved in saline and fasted for 16h. N-Acetylcysteine (NAC, 500 mg/kg) was used as a positive control. The activities of serum alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) increased significantly 4 h after APAP administration. Oral administration of crude water extract of Vetiveria root at a dose of 0.9 g/kg before or after the oral administration of APAP significantly reduced (P<0.05) the elevated values of serum ALT, AST, ALP and hepatic morphologic changes induced in mice. Antioxidant status, reduced glutathione (GSH), glutathione reductase (GR) and glutathione S-transferase (GST) were reduced significantly (P<0.05) and the lipid peroxidation and the activity of GPx were enhanced significantly in the APAP treated group. Vetiveria root extract markedly inhibited lipid peroxidation, oxidation of glutathione and enhanced the activities of GR and GST in mouse liver homogenate (P<0.05). Although the effects of NAC and Vetiveria root extracts were comparable in replenishing GSH in APAP toxicity, pre or post-treatment with Vetiveria showed better effects on GR and GST levels in liver homogenates. Hepatoprotective effect of the crude water extract of Vetiveria root against APAP induced acute toxicity may be mediated by preventing the decline of hepatic antioxidant status.