The effects of milk thistle on hepatic fibrosis due to methotrexate in rat

Background: Extracts of milk thistle (MT), Silybum marianum, have been used as medical remedies since the time of ancient Greece. Methotrexate is a potentially hepatotxic drug. Objectives: To clarify the hepatoprotective effects of MT on methotrexate. Materials and Methods: From January 2010 to April 2010, 30 male rats were recruited into three 10-rat subgroups in Tabriz University of Medical Sciences. Normal saline was injected intraperitoneally in the first group (A; the controls); intraperitoneal methotrexate plus oral MT extract were administered to the second group (B) and intraperitoneal methotrexate alone was given to the third group (C). Pre- and post-interventional measuring of serum parameters were carried out every 15 days. After six weeks, the rats were decapitated and histopathological evaluation of liver was done. Results: Serum liver enzymes (AST, ALT), alkaline phosphatase, total and direct bilirubin, creatinine and BUN were measured on days 0, 15, 30, 45. They were significantly higher in the group C, comparing with other two groups. Serum albumin was the least in group C animals as well. There were no significant differences between groups A and B. The mean±SD fibrosis score using semi-quantitative scoring system (SSS) was 1.25±0.46, 1.40±0.52 and 6.70±0.82, in groups A, B and C, respectively (p<0.001). Conclusions: MT extract can effectively prevent methotrexate-induced liver dysfunction and fibrosis in rats.