Comparative hepatoprotective activity of Fumaria farviflora Lam. leaf extract and silymarin on isoniazid and rifampicin-induced hepatotoxic rats

Abstract

Isoniazid and rifampicin are first line drugs used for the treatment of tuberculosis but their use is associated with potentially serious toxic manifestation in the liver leading to necrosis, cirrhosis and hepatitis causing poor patient compliance. The present study was conducted to evaluate hepatoprotective activity of Fumaria parviflora leaf extract in isoniazid and rifampicin-induced hepatotoxic rats. Acute toxicity was conducted with single oral doses of F. parviflora leaf extracts at 300, 2000 and 5000 mg/kg and rats were observed for changes in body weight, haematological parameters, behavioural changes and signs of toxicity. Hepatoprotective activity of F. parviflora leaf extract (100, 200 and 300 mg/kg, p.o.) was evaluated on isoniazid and rifampicin (50 mg/kg, i.p.) induced hepatotoxic rats using silymarin as a reference drug (100 mg/kg, p.o.). F. parviflora leaf extract was found to be safe up to 5 g/kg. From biochemical and histopathological parameters it was found that pretreatment of rats with F. parviflora leaf extract an hour prior to start isoniazid and rifampicin resulted in a significant decline in the serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and total bilirubin as well as normal histology of liver biopsy specimens. It was concluded that F. parviflora leaf extract has significant hepatoprotective activity at the dose of 200 mg/kg comparable with that of silymarin. The plant extract appeared to have the potential to be used as a dietary supplement to antiTB therapy to protect against the hepatotoxicity of isoniazid and rifampicin.