Protective effects of curcumin, α-lipoic acid, and N-acetylcysteine against carbon tetrachloride-induced liver fibrosis in rats.

Liver fibrosis is a major health problem that can lead to the development of liver cirrhosis and hepatocellular carcinoma. On the other hand, several antioxidants have been shown to possess protective effect against liver fibrosis. Therefore, in the present work, the effectiveness of curcumin, α-lipoic acid, and N-acetylcysteine in protecting against carbon tetrachloride (CCl(4))-induced liver fibrosis as well as the mechanism(s) implicated in this protective effect was studied. The antioxidants used in this study resulted in hepatoprotective effect as evident by substantial decreases in collagen deposition in histopathological examinations in addition to significant decrease in serum levels of alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transpeptidase, bilirubin, and transforming growth factor-alpha (TGF-α) as well as hepatic malondialdehyde concentration, with a concurrent increase in serum matrix metalloproteinase-13 (MMP-13) and hepatic reduced glutathione (GSH) levels as compared to CCl(4) fibrotic group. In conclusion, curcumin, α-lipoic acid, and N-acetylcysteine protect rats against CCl(4)-induced liver fibrosis most possibly through their antioxidant activities and their capacities to induce MMP-13 and to inhibit TGF-α levels.