RESUMO
OBJECTIVE: Hepatotoxicity is one of the major side effects of methotrexate and limits its use. In this study, we investigated the hepatoprotective effect of silibinin and the role of oxidative stress markers and cytokines on high-dose methotrexate-induced hepatotoxicity in rats. MATERIALS AND METHODS: In this study, rats were randomly divided into 5 groups (n=7). Methotrexate (20 mg/kg, intraperitoneally) was administered on the first day in all groups except control. Silibinin was injected for 5 days to methotrexate-silibinin25, methotrexate-silibinin50, and methotrexate-silibinin100 groups at a dose of 25, 50, and 100 mg/kg/day, respectively. On the sixth day, blood and liver samples were obtained and rats were sacrificed. Serum total antioxidant capacity, total oxidant status, total thiol, native thiol, alanine aminotransferase, aspartate transaminase, bilirubin, albumin, tumor necrosis factor-alpha, and interleukin-10 levels were measured. In addition, a histopathological evaluation of liver tissues was performed. RESULTS: Methotrexate reduced total antioxidant capacity and increased disulfide/total thiol ratio. Histopathologic examination revealed that methotrexate increased hepatic damage and 50 mg/kg/dose of silibinin prevented inflammatory cell infiltration in particular. CONCLUSION: Our results suggest that silibinin (50 mg/kg/day) may reduce the hepatic damage in methotrexate-induced hepatotoxicity in rats by increasing antioxidant capacity.
