Jiawei Taohe Chengqi Decoction attenuates CCl4 induced hepatic fibrosis by inhibiting HSCs activation via TGF-ß1/CUGBP1 and IFN-γ/Smad7 pathway.

ABSTRACT

BACKGROUND: Hepatic fibrosis (HF) is an essential stage in the progression of different chronic liver conditions to cirrhosis and even hepatocellular carcinoma. The activation of hepatic stellate cells (HSCs) plays a crucial role in the progression of HF. IFN- γ/Smad7 pathway can inhibit HSCs activation, while TGF-ß1/CUGBP1 pathway can inhibit IFN-γ/Smad7 pathway transduction and promote HSCs activation. Thus, inhibiting the TGF-ß1/CUGBP1 pathway and activating the IFN-γ/Smad7 pathway reverses HSCs activation and inhibits HF. Jiawei Taohe Chengqi Decoction (JTCD) was derived from the Taohe Chengqi Tang in the ancient Chinese medical text titled "Treatise on Febrile Diseases". We found several anti-HF components in JTCD including ginsenoside Rb1 and others, but the specific mechanism of anti-HF in JTCD is not clear. PURPOSE: To elucidate the specific mechanism by which JTCD reverses HF by inhibiting the activation of HSCs, and to establish a scientific foundation for treating HF with Traditional Chinese medicine (TCM). METHODS: We constructed a CCl4-induced mice HF model in vivo and activated human hepatic stellate cell line (LX-2) with TGF-ß1 in vitro, after which they were treated with JTCD and the corresponding inhibitors. We examined the expression of pivotal molecules in the two pathways mentioned above by immunofluorescence staining, Western blotting and RT-PCR. RESULTS: JTCD attenuated liver injury and reduced serum ALT and AST levels in mice. In addition, JTCD attenuated CCl4-induced HF by decreasing the expression of α-SMA, COL1A1 and other markers of HSCs activation in mice liver tissue. Moreover, JTCD effectively suppressed the levels of TGF-ß1, p-Smad3, p-p38MAPK, p-ATF2, and CUGBP1 in vivo and in vitro and upregulated the levels of IFN-γ, p-STAT1, and Smad7. Mechanically, after using the inhibitors of both pathways in vitro, we found that JTCD inhibited the activation of HSCs by restoring the balance of the TGF-ß1/CUGBP1 and IFN-γ/Smad7 pathways. CONCLUSION: We demonstrated that JTCD inhibited HSCs activation and reversed HF by inhibiting the TGF-ß1/CUGBP1 signalling pathway and upregulating the IFN-γ/Smad7 signalling pathway. Moreover, we have identified specific links where JTCD interferes with both pathways to inhibit HSCs activation. JTCD is an effective candidate for the clinical treatment of HF.