Hepatoprotective effect of cold-pressed Syzygium aromaticum oil against carbon tetrachloride (CCl4)-induced hepatotoxicity in rats

Contexts: Exposure to environmental pollutants such as carbon tetrachloride (CCl4) causes liver injuries. There are claims that extracts from Syzygium aromaticum (Linn.) Merrill & L.M.Perry, (Myrtaceae) protects from such injuries. Objective: This study investigates the protective effects of cold-pressed S. aromaticum oil (CO) against CCl4-induced liver toxicity in rats. Materials and methods: CO was orally administered to rats in two doses (100 and 200mg/kg) along with CCl4 (1 mL/kg in olive oil) for 8 weeks. Indices of liver and kidney functions, lipid profile, and peroxidation were evaluated in rats' serum and tissues. Fatty acids and bioactive lipids of CO were analyzed. Results: High levels of monounsaturated fatty acids (39.7%) and polyunsaturated fatty acids (42.1%) were detected in CO. The oil contained high amounts of tocols and phenolics. The LD50 value at 24 h was approximately 5950 mg/kg. Treatment with 200mg/kg CO resulted in a decrease of creatinine, urea, and uric acid levels to 0.86, 32.6, and 2.99 mg/dL, respectively. Levels of TL, TC, TAG, LDL-C, and VLDL-C were decreased to 167, 195.3, 584.5, 74.6, and 39.0 mg/L, respectively, after 8 weeks of treatment. Hepatic malondialdehyde levels were reduced and glutathione levels were elevated in CO-treated rats. CO reduced the activities of AST, ALT, and ALP as well as kidney function markers, protein, and lipid profiles, respectively. Histopathological examination of liver indicated that CO treatment reduced fatty degenerations, cytoplasmic vacuolization, and necrosis. Conclusion: CO possessed a protective effect against CCl4-induced hepatotoxicity in rats, mediated possibly by the antioxidant properties of the oil.