Abstract
OBJECTIVE: The study was designed to investigate the hepatoprotective activity of methanol extract of Cissus quadrangularis (CQ) against isoniazid-induced hepatotoxicity in rats. MATERIALS AND METHODS: The successive petroleum ether (60-80°C) and methanol extracts of C. quadrangularis were used. Hepatic damage was induced in Wistar rats by administering isoniazid (54 mg/kg, p.o.) once daily for 30 days. Simultaneously, CQ (500 mg/kg p.o) was administered 1 h prior to the administration of isoniazid (54 mg/kg, p.o.) once daily for 30 days. Silymarin (50 mg/kg p.o) was used as a reference drug. RESULTS: Elevated levels of aspartate transaminase, alanine transaminase, alkaline posphatase, and bilirubin following isoniazid administration were significantly lowered due to pretreatment with CQ. Isoniazid administration significantly increased lipid peroxidation (LPO) and decreased antioxidant activities such as reduced glutathione, superoxide dismutase, and catalase. Pretreatment of rats with CQ significantly decreased LPO and increased the antioxidant activities. CONCLUSION: The results of this study indicated that the hepatoprotective effect of CQ might be attributed to its antioxidant property.