Abstract
The aim of this study was to evaluate and compare the effects of imatinib and nilotinib to that of silymarin on established liver fibrosis and oxidative stress in a thioacetamide (TAA) rat model. Male Wistar rats received intraperitoneal (i.p.) injections of TAA (150 mg/kg, twice weekly) for 12 weeks. Daily treatments with imatinib (10 mg/kg), nilotinib (10 mg/kg), and silymarin (100 mg/kg) were administered orally during the last 4 weeks of TAA-administration. At the end of the study, hepatic damage was evaluated by analysis of liver function tests in serum. Hepatic histopathology and collagen content were employed to quantify liver fibrosis. Hepatic oxidative stress was assessed by measuring malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), total nitrate/nitrite (NOx), and reduced glutathione (GSH) contents, as well as myeloperoxidase (MPO) and superoxide dismutase (SOD) activities. Nilotinib, silymarin and, to a lesser extent, imatinib treatments ameliorated TAA-induced hepatic oxidative stress and damage as indicated by hepatic MDA, 4-HNE, NOx, GSH, MPO and SOD levels, as well as liver function tests. Hepatic histopathology results revealed that nilotinib, imatinib, and silymarin treatments decreased the mean score of fibrosis in TAA-treated rats by 24, 14, and 3%, respectively. However, nilotinib and silymarin, but not imatinib, treatments decreased hepatic collagen content in TAA-treated rats by 17 and 36%, respectively. In conclusion, we demonstrated for the first time that nilotinib not only protected against hepatic oxidative stress, but also slowed down liver fibrosis progression. Thus, we provide the first evidence that nilotinib might be a promising anti-fibrotic drug.