The study was designed to investigate the hepatoprotective activity of methanol extract of Cissus quadrangularis against rifampicin-induced hepatotoxicity in rats.The coarse powder of the shade dried stem of Cissus quadrangularis was subjected to successive extraction in a Soxhlet apparatus using solvents petroleum ether (60-80°) and methanol. Liver damage was induced in Wistar rats by administering rifampicin (54 mg/kg, p.o.) once daily for 30 days. Methanol extract of Cissus quadrangularis (500 mg/kg, p.o) was administered 1 h prior to the administration of rifampicin (54 mg/kg, p.o.) once daily for 30 days. Silymarin (50 mg/kg p.o) used as reference drug. Elevated levels of aspartate transaminase, alanine transaminase, alkaline posphatase and bilirubin following rifampicin induction were significantly lowered due to pretreatment with methanol extract of Cissus quadrangularis. Rifampicin administration significantly increased lipid peroxidation and decreased antioxidant activities like reduced glutathione, superoxide dismutas and catalase. Pretreatment of rats with methanol extract of Cissus quadrangularis significantly decreased lipid peroxidation and increased the antioxidant activities. Histology of the liver section of the animals treated with the methanol extract of Cissus quadrangularis further confirms the hepatoprotective activity. The results of the present study indicated the hepatoprotective effect of methanol extract of Cissus quadrangularis which might be ascribable to its antioxidant property due to the presence of β-carotene.
Keywords: Cissus quadrangularis; hepatotoxicity; rifampicin; β-carotene.