Context: Different parts of the walnut [Juglans regia L. (Juglandaceae)] have been used in folk medicine for protection against liver injury, although its actual efficacy remains uncertain.
Objective: The present study investigated the protective effect of walnut leaf extract against carbon tetrachloride (CCl4)-induced liver damage in rats.
Materials and methods: The rats were randomly divided into seven groups: control, CCl4 (i.p., 0.5 mL/kg b.w., 50% CCl4 in olive oil), walnut extract (at dose level of 0.2 g/kg b.w.) alone, walnut extract (at dose levels of 0.05, 0.1, 0.2 and 0.4 g/kg b.w.) with CCl4, and treatment was carried out accordingly. On the 28th day, rats were sacrificed and blood was withdrawn by cardiac puncture. Liver damage was assessed by serum biochemical parameters (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and albumin), antioxidant enzymes (superoxide dismutase and catalase) and histopathological observation.
Results: Administration of walnut leaf extract (ranging from 0.2 to 0.4 g/kg b.w.) significantly lowered serum alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase levels in CCl4-treated rats. Walnut leaf extract increased antioxidant enzymes, including superoxide dismutase and catalase. Histopathological examination of livers showed that walnut leaves extract reduced fatty degeneration, cytoplasmic vacuolization and necrosis in CCl4-treated rats.
Discussion and conclusion: These results suggest that walnut extract has a protective effect over CCl4-induced oxidative damage in rat liver. These results demonstrate that walnut extract acts as a good hepatoprotective and antioxidant agent in attenuating hepatocellular damage.