Modulatory potentials of aqueous leaf and unripe fruit extracts of Carica papaya Linn. (Caricaceae) against carbon tetrachloride and acetaminophen-induced hepatotoxicity in rats

INTRODUCTION Carica papaya Linn is used in a traditional medicine for hepatobiliary disorders. This study investigated the hepatomodulatory effects of aqueous extracts of C. papaya leaf (CPL) and unripe fruit (CPF) at doses of 100 and 300 mg/kg on carbon tetrachloride (CCl4) and acetaminophen (ACM)-induced liver toxicities in rats. MATERIALS AND METHODS Rats were administered CCl4 (3 ml/kg in olive oil, i.p.) followed by oral administration of CPL and CPF at 2, 6 and 10 h intervals. The ACM model proceeded with the same method but inclusive of animals treated with N-acetyl cysteine (3 ml/kg i.p). At the end of the study, serum levels of liver biomarkers and antioxidant enzymes were assessed and histology of the liver tissues determined. RESULTS There was a significant (P < 0.05) reduction in CCl4 and ACM-induced increases in serum levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and direct bilirubin at 100 and 300 mg/kg, respectively. The levels of catalase (CAT), superoxide dismutase and reduced GSH were decreased in both models with corresponding significantly (P < 0.05) elevated level of malondialdehyde. However, these antioxidant enzymes were significantly (P < 0.05) increased in CPL and CPF-treated rats. Histopathological assessment of the liver confirmed the protective effects of CPL and CPF on CCl4 and ACM-induced hepatic damage evidenced by the normal presentation of liver tissue architecture. CONCLUSION These results indicate that aqueous extracts of C. papaya may be useful in preventing CCl4 and ACM-induced liver toxicities.