Regression of liver fibrosis by taurine in rats fed alcohol: Effects on collagen accumulation, selected cytokines and stellate cell activation

The antifibrogenic effect of taurine in experimental liver fibrosis has been shown. The role of taurine to abate fibrogenic mediators and collagen deposition during liver fibrosis induced by simultaneous administration of iron carbonyl (0.5% w/w) and alcohol (6 g/kg/day) was investigated in this study. Liver histology, the levels of inflammatory cytokines, stellate cell activation, oxidative stress and collagen content were assessed. Liver fibrosis and a rise in collagen content in ethanol plus iron-fed rat were evident from van Gieson and Masson's trichrome staining respectively. Hepatic myeloperoxidase activity and plasma levels of interleukin-6 (IL-6) and tumor necrosis factor-a (TNF-alpha) were markedly elevated. This was associated with an imbalance in the oxidant-antioxidant system, increased expression of transforming growth factor-beta(1) (TGF-beta(1)) and stellate cell activation suggested by a-smooth muscle actin (alpha-SMA) localization. This condition was protected in the presence of taurine. Taurine lowered the levels of IL-6, TNF-alpha and peroxidation products and the expression of alpha-SMA, desmin and TGF-beta(1) and improved the antioxidant status. A positive relationship between hepatic collagen with iron and lipid peroxides and an inverse relationship between collagen and glutathione were noted. It is concluded that taurine reduces iron-potentiated alcoholic liver fibrosis by curtailing oxidative stress, production of inflammatory and fibrogenic mediators and activation of stellate cells. (c) 2010 Elsevier B.V. All rights reserved.