Phillygenin Ameliorates Carbon Tetrachloride-Induced Liver Fibrosis: Suppression of Inflammation and Wnt/β-Catenin Signaling Pathway

Liver fibrosis (LF) is caused by the chronic wound healing response to liver injury from various origins. Among the causes, inflammatory response is the central trigger of LF. Phillygenin ( PHI) is a lignan derived from Forsythia suspensa, which has significant anti-inflammatory properties. However, the effect of PHI on improving LF and the underlying mechanism have rarely been studied. In this study, we used carbon tetrachloride (CCl4) to establish a mouse model of LF. Through histological analysis of liver tissue, and measurement of the levels of hepatocyte damage markers (ALT, AST, TBIL, TBA) and four indicators of LF (Col IV, HA, LN, PC-III) in serum, it was shown that PHI improved liver function and reduced the progress of LF. Subsequently, the detection of fibrogenic biomarkers in liver tissue showed that PHI inhibited the activation of hepatic stellate cells (HSCs). Next, the expression of inflammatory markers in liver tissue/serum was detected by immunohistochemistry, RT-qPCR, and ELISA, suggesting that PHI inhibited inflammation during LF. Similarly, in vitro experiments also confirmed that PHI could inhibit lipopolysaccharide-induced inflammatory responses in RAW264.7 cells, which showed strong anti-inflammatory effects. In addition, the results of network pharmacology, molecular docking, RT-qPCR and western blot confirmed that PHI could alleviate CCl4-induced LF by inhibiting the Wnt/beta-catenin pathway. In conclusion, our research showed that PHI curbed LF through inhibition of HSC activation and collagen accumulation via inhibiting multiple profibrogenic factors, modulating a variety of inflammatory factors, and suppressing the Wnt/beta-catenin pathway.