Evaluation of Hepatoprotective Activity of the Crude Extract and Solvent Fractions of Clutia abyssinica ( Euphorbiaceae) Leaf Against CCl ₄-Induced Hepatotoxicity in Mice

Background: Liver is a vital organ that plays a major role in the elimination of xenobiotics from the body. Diseases that affect the liver become major health problems and challenge health-care professionals as well as the pharmaceutical industry. Since the conventional treatment of liver diseases is associated with a wide range of adverse effects, botanical agents are commonly used. Among these agents, Clutia abyssinica is the most widely used herb in Ethiopian traditional medicine.

Objective: To evaluate the hepatoprotective activity of the crude 80% methanol extract and solvent fractions of Clutia abyssinica leaves in mice.

Methods: The leaves of Clutia abyssinica were extracted by cold maceration using 80% methanol as a solvent, and the solvent fractions were obtained in liquid-liquid extraction with chloroform, n-butanol and distilled water. Male mice were treated with the vehicles (distilled water or 2% Tween 80), three different doses (100, 200 and 400 mg/kg) of the crude 80% methanol extract and three solvent fractions, the standard drug (silymarin 100 mg/kg), and the hepatotoxicant carbon tetrachloride (CCl₄). Then, the levels of biomarkers of liver injury - such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) - and liver function such as total protein, albumin, and bilirubin were measured. Evaluation of the change in body weight and liver weight, histopathologic examination and in vitro antioxidant assay against CCl₄-induced hepatotoxicity were also carried out.

Results: The 80% methanol extract decreased the absolute and relative weight of the liver of mice at the doses of 200 and 400 mg/kg (p<0.01 and p<0.001, respectively). It also suppressed the plasma levels of AST, ALT and ALP (p<0.001) in the aforementioned doses. Among fractions, the n-butanol fraction showed maximum hepatoprotective activity in its dose of 200 and 400 mg/kg (p<0.001, in all cases). Likewise, the chloroform fraction (400 mg/kg) reduced to a similar extent (p<0.001 in all cases). In stark contrast, the aqueous fraction failed to affect the levels of all biomarkers of hepatocyte injury. The crude methanol extract and n-butanol fraction were able to return the normal hepatic architecture of hepatocytes and scavenge free radicals in the 1,1-diphenylpicrylhydrazyl (DPPH) assay.

Conclusion: Clutia abyssinica is endowed with hepatoprotective activity, probably mediated via its antioxidant activity. Thus, Clutia abyssinica can be taken as one candidate for the development of hepatoprotective agents because of its good safety profile.

Keywords: CCl4; Clutia abyssinica; antioxidant; hepatoprotective; mice.