Abstract: AIM: To explore the protective effect of fluorofenidone (AKF-PD) on diethylnitrosamine-induced liver injury in rats and its inhibition of the TGF-β1/Smads pathway in hepatocytes.  METHODS: Fifty-five male Sprague Dawley (SD) rats were randomly divided into three groups: model group (DEN group, n=20) were gavaged with DEN (10 mg/kg), 5 times for 14 weeks; control group (n=20) were gavaged with saline with the same volume of the model group; treatment group (DEN+AKF-PD Group, n=15), after 4 weeks of modeling, they were gavaged with AKF-PD (500 mg/kg) daily, and stopped at 14 weeks. At the end of experiment, the rats were killed by anesthesia and spinal dislocation. Masson staining was used to observe collagen deposition; primary hepatocytes were extracted and identified, and the levels of α-smooth muscle actin (α-SMA), TGF-β1, Smad3, and Smad7 mRNA, and the expression of Smad3 and Smad7 proteins in hepatocytes were detected. RESULTS: Compared with the control group, Masson staining showed that collagen deposition increased in the DEN group; AKF-PD treatment could significantly improve liver pathological damage and reduce collagen deposition. In addition, compared with the DEN group, the α-SMA, TGF-β1, and Smad3 mRNA levels of the AKF-PD group were significantly reduced, and the Smad7 mRNA level was increased. Moreover, AKF-PD treatment could dependably reduce the expression of Smad3 and increase Smad7. CONCLUSION: AKF-PD can significantly improve liver injury and fibrosis in rats caused by DEN. This effect may be related to the down-regulation of α-SMA, TGF-β1, and Smad3 mRNA levels in hepatocytes and the increase of Smad7 mRNA levels.

Key words: flufenidone, liver fibrosis, TGF-β1/Smads pathway, hepatocytes