Fluorofenidone affects hepatic stellate cell activation in hepatic fibrosis by targeting the TGF-β1/Smad and MAPK signaling pathways

The aim of the present research was to study the therapeutic impacts of fluorofenidone (AKF-PD) on pig serum (PS)-induced liver fibrosis in rats and the complex molecular mechanisms of its effects on hepatic stellate cells (HSCs). Wistar rats were randomly divided into normal control, PS and PS/AKF-PD treatment groups. The activated human HSC LX-2 cell line was also treated with AKF-PD. The expression of collagen I and III, and alpha-smooth muscle actin (alpha-SMA) was determined by immunohistochemical staining and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Western blotting and/or RT-qPCR analyses were used to determine the expression of transforming growth factor (TGF)-beta 1, alpha-SMA, collagen I, mothers against decapentaplegic homolog (Smad)-3, extracellular signal-regulated kinase (ERK)1/2, p38 mitogen-activated protein kinase (p38 MAPK) and c-Jun N-terminal kinase (JNK). AKF-PD attenuated the degree of hepatic fibrosis and liver injury in vivo, which was associated with the downregulation of collagen I and III, and alpha-SMA at the mRNA and protein levels. In vitro, AKF-PD treatment significantly reduced the TGF-beta 1-induced activation of HSCs, as determined by the reduction in collagen I and alpha-SMA protein expression. The TGF-beta 1-induced upregulation of the phosphorylation of Smad 3, ERK1/2, p38 and JNK was attenuated by AKF-PD treatment. These findings suggested that AKF-PD attenuated the progression of hepatic fibrosis by suppressing HSCs activation via the TGF-beta 1/Smad and MAPK signaling pathways, and therefore that AKF-PD may be suitable for use as a novel therapeutic agent against liver fibrosis.