RESUMO
CONTEXT: Hippocratea africana (Willd.) Loes. ex Engl. (Celastraceae) root is used traditionally as an antipoison or antidote to treat liver diseases. OBJECTIVE: To evaluate antioxidative burst and hepatoprotective potentials of H. africana against paracetamol-induced liver injury in rats. MATERIALS AND METHOD: Antioxidative burst activity of the extract (1-100 µg/ml) in whole blood, neutrophils and macrophages was investigated using a luminol/lucigenin-based chemiluminescence assay. The hepatoprotective effect of the extract (200-600 mg/kg) was evaluated by the assay of liver function parameters, antioxidant enzymes and histopathological studies of the liver. GC-MS analyses of hexane and dichloromethane fractions were also carried out. RESULTS AND DISCUSSION: The root extract/fractions exerted pronounced inhibition of oxidative burst activity in whole blood, neutrophils (intracellular and extracellular) and macrophages (3.04-99.70%). The administration of the root extract caused significant (p < 0.05-0.001) reduction of high levels of liver enzymes (AST, ALT and ALP), total cholesterol, direct and total bilirubin as well as elevation of serum levels of total protein, albumin and antioxidant enzymes (SOD, CAT, GPx and GSH). Histology of the liver sections of extract and silymarin-treated animals showed reductions in the pathological features compared to the paracetamol-treated animals. The chemical pathological changes were consistent with histopathological observations suggesting a marked hepatoprotective effect of the root extract of H. africana. The GC-MS analysis revealed some pharmacologically active compounds. CONCLUSION: The results show that the root extract of H. africana has hepatoprotective potential probably due to its antioxidative burst activity.
