Background: The objective of present study was to evaluate the hepatoprotective effect against liver injury induced by CCl₄ as well as in-vitro anti-oxidant property assessed by reducing power capacity (RPA) of hexane, ethanol extracts along with pure compound piperine, extracted from fruits of Piper nigrum L.

Methodology: This pre-clinical animal study estimates the prophylactic and therapeutic hepatoprotective effect of hexane and ethanol leaves extracts along with pure compound piperine extracted from fruits of Piper nigrum. Both sexes of albino rats were distributed into a normal control group, a CCl₄ hepatotoxicity control group (receiving single oral dose of CCl₄ 1.5 ml/kg body weight) in equal volume of olive oil (1:1) and nine treatment groups receive hexane and ethanol leaves extracts (75, 150, 250 mg/kg body weight) and pure compound piperine (25, 75, and 100 mg/kg body weight) along with toxicant CCl_4. Standard drug (Betaine Glucuronate + Diethanolamine Glucuronate + Nicotinamide Ascorbate) treated group (5.37, 10.75, 16.13 mg/kg body weight) along with toxicant CCl₄. Orally for five consecutive days. Liver damage was assessed by the biochemical estimation of serum activities of hepatic enzymes Alkaline phosphatese (ALP), Alanine aminotransferase (ALT), Gamma-glutamyl transferase (γ-GT), Direct bilirubin (DB) and Total Bilirubin (TBL). These tests are referred to as liver function test (LFT). This investigation test was supported by histopathological examinations. While tested extracts and compound were also analyzed for anti-oxidant capacity using reducing power ability (RPA). The reducing power assay applied to regulate the potential of an anti-oxidant to donate an electron.

Results: The estimation of hepatoprotective effect of test samples showed a potential of liver protection both in prophylactic and therapeutic model in a dose dependent manner against liver injury induced by CCl_4. But more significant results of enzymes suppression were seen in prophylactic model by piperine at a dose of 100 mg/kg body weight. This was an effective investigation test with high negative prognostic value of liver diseases that were supported with histopathological examination of rat liver section. Moreover, Piperine exhibited the highest reducing power capacity measured by RPA assay among all tested samples but less than standard drug ascorbic acid.

Conclusion: Piper nigrum L. fruit can be used as an effective hepatoprotective agent both in prophylactic and therapeutic models along with antioxidant potential.

Keywords: Anti-oxidant, Biochemical parameters, Carbon tetrachloride, Hepatoprotective, Histopathological examination.