Eucalyptol Protects against Cisplatin-Induced Liver Injury in Rats

Eucalyptol (1,8-cineole), a terpenoid oxide, is known as the main component of eucalyptus essential oils. The antimicrobial, anti-inflammatory and antioxidant activities of eucalyptol have been reported in many studies. We investigated the possible effects of eucalyptol (EUC) against hepatotoxicity induced by cisplatin (CIS) in Wistar albino rats. A total of 24 rats were divided into 4 equal groups; Control (C), Eucalyptol (EUC), Cisplatin (CIS), and Cisplatin + Eucalyptol (CIS + EUC). CIS and CIS + EUC groups received cisplatin (12 mg/kg, in a single dose, intraperitoneally (i.p.)). EUC and CIS + EUC groups were treated with eucalyptol (100 mg/kg, seven days, orally). The rats were euthanised under appropriate conditions, and samples were taken. Histopathologically, hepatocyte degeneration and necrosis, sinusoidal dilatation, inflammatory cell infiltration and bile duct proliferation were significantly irregular in the CIS group compared to the C group. However, EUC treatment modulated changes in group CIS. Biochemically, EUC (100 mg/kg) treatment reduced oxidative stress against increased liver hepatotoxicity by decreasing MDA levels and increasing Glutathione (GSH), Glucose-6-phosphate dehydrogenase (G6PD) and Catalase (CAT) levels. EUC treatment down-regulated 8-hydroxy-2-deoxyguanosine (8-OHdG) levels, resulting in reductions DNA damage. It also significantly down-regulated inducible nitric oxide synthase (iNOS) expression. In conclusion, eucalyptol exerts protective effects on cisplatin-induced experimental liver toxicity in rats by improving oxidative stress and oxidative DNA damage and iNOS expressions.