Abstract

Hepatoprotective effect of Garcinia kola seed extract on oxidative stress and hepatotoxicity biomarkers of rats exposed to antitubercular drugs was investigated to evaluate its potential to ameliorate drug-induced hepatotoxicity. Six groups of five animals each were used. Combination of Isoniazid (7.5 mg/kg bodyweight) and Rifampicin (10 mg/kg bodyweight) was administered intraperitoneally to a group. Drug combination was co-administered with G. kola seed extracts (40, 60 and 80 mg/kg bodyweight) to three other groups for 35 days. Control group received saline and the last group received G. kola alone (60 mk/kg bodyweight). Plasma oxidative stress biomarkers (superoxide dismutase, glutathione, glutathione peroxidase, catalase and malondialdehyde) and hepatotoxicity biomarkers (alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase) were assayed after treatment. The antitubercular drugs significantly increased levels of hepatotoxicity biomarkers. The increase was mitigated by treatment with G. kola, with reduction in levels of the hepatotoxicity biomarkers upon G. kola co-administration. Similarly, the antitubercular drugs reduced the activities of oxidative stress biomarkers. Histomorphological analysis of the liver showed that the G. kola extract administered at 60 mg/kg offered significant protection from exposure to the hepatotoxic drugs. The study concluded that G. kola extract at 60 mg/kg significantly protected the animals from the damages occasioned by exposure to hepatotoxic antitubercular drugs.

Key words: Isoniazid, rifampicin, tuberculosis, hepatotoxicity, hepatoprotection, histomorphology.