JTCD attenuates HF by inhibiting activation of HSCs through PPARα-TFEB axis-mediated lipophagy.

Background: Hepatic fibrosis (HF) is an intermediate stage in the progression of chronic liver disease to cirrhosis and has been shown to be a reversible pathological process. Known evidence suggests that activation of hepatic stellate cells (HSCs) and degradation of their lipid droplets (LDs) play an indispensable role in the process of HF. Jiawei Taohe Chengqi Decoction (JTCD) can inhibit the activation of HSCs in the process of HF, but the exact mechanism remains to be elucidated.

Purpose: The aim of this study is to determine whether JTCD inhibits lipophagy and to explore the possible mechanisms of its HF effect in HSCs by regulating the PPARα/TFEB axis.

Methods: Network pharmacology and molecular docking were firstly applied to predict the potential mechanism of JTCD for the treatment of HF. In vivo, a mouse model of HF was constructed using carbon tetrachloride (CCl) solution, and the efficacy of JTCD was assessed by staining of pathological sections, oil red O staining, immunofluorescence (IF), immunohistochemistry (IHC) staining, Western blotting and qRT-PCR. The intervention of JTCD was verified in vitro by induction of activated LX-2 cells with TGF-β solution and intervention using agonists and antagonists of PPARα. Finally, transient transfection of cells using TFEB siRNA was performed for validation studies.

Results: JTCD effectively alleviated CCl-induced HF in mice and reduced the levels of HF markers α-smooth muscle actin (α-SMA) and collagen I (COL1A1), and inhibited PPARα expression and lipophagy process. In vitro, JTCD delayed the degradation of LDs and reduced lipophagy in LX-2 cells, suggesting a mechanism involving PPARα/TFEB axis signaling regulation.