Amelioration of Liver Fibrosis via In Situ Hepatic Stellate Cell Conversion Through Co-Inhibition of TGF-β and GSK-3 Signalling.

BACKGROUND AND AIMS: Liver fibrosis, a progressive condition driven by chronic liver injury and excessive scar tissue formation, can lead to cirrhosis, a life-threatening disease. Activation of hepatic stellate cells (HSCs) is central to fibrosis progression, yet current therapies fail to halt or reverse this process. This study evaluated a combination therapy targeting HSCs to ameliorate fibrosis and promote liver repair.

METHODS: A small molecule cocktail, SBCH (SB431542, a TGF-β inhibitor, and CHIR99021, a GSK-3 inhibitor), was tested in three fibrosis models: CCl4-induced, bile duct ligation (BDL) and non-alcoholic steatohepatitis (NASH) with diethylnitrosamine (DEN). Therapeutic effects were assessed using phenotypic analyses, in vivo tracing and single-cell RNA sequencing to uncover mechanisms.

RESULTS: SBCH significantly reduced fibrosis in all models by inhibiting HSC activation and fibrogenic activity. The suppression of PI3K/Akt pathway and EMT cascade contribute to the fibrosis-ameliorating effect of SBCH treatment. Furthermore, in vivo tracing and single-cell RNA sequencing revealed that SBCH induced the conversion of activated HSCs into hepatocyte-like cells (ciHeps), which integrated into liver tissue, repaired liver damage and restored liver integrity and function.

CONCLUSIONS: SBCH mitigates liver fibrosis through multifaceted mechanisms, including the inhibition of HSC activation, suppression of fibrogenic activity and regulation of key signalling pathways such as PI3K/Akt and EMT. In addition, SBCH induces the trans-differentiation of activated HSCs into hepatocyte-like cells (ciHeps), effectively reducing pathogenic HSCs while increasing functional ciHeps. This dual-target approach not only facilitates liver tissue repair but also restores liver function, offering a promising therapeutic strategy for liver fibrosis and cirrhosis, with potential applications in conditions arising from various aetiologies of liver injury.