Compound Gardenia Radix Granule mitigates liver fibrosis in CCl4-induced mice by repressing SphK1-S1PR2 axis-mediated p-ERK signaling.

BACKGROUND

Liver fibrosis (LF) could be alleviated by Compound Gardenia Radix Granule (CGRG), an in-hospital traditional Chinese medicine preparation approved by the Fujian Provincial Medical Products Administration (FPMPA, Fujian, China; Approval No.: Z04202044). However, its mechanism of action remains elusive.

PURPOSE: To evaluate the anti-LF efficacy of CGRG and its molecular mechanisms.

METHODS

CGRG compounds were analyzed by ultrahigh performance liquid chromatography paired with Quadrupole-Orbitrap High-Field Mass Spectrometry (UHPLC-Q Exactive HF-MS) and evaluated by network pharmacology to identify compounds, targets, and potential signaling pathways. The anti-fibrotic effects of CGRG were assessed in a carbon tetrachloride (CCl4)-induced mouse model and in mouse hepatic stellate cells (JS-1). Transcriptome and metabolome analyses of the mouse liver were performed to identify differentially expressed genes and metabolites, respectively. Enriched KEGG pathways were identified and validated by RNA interference, western blot analysis, and using pharmacological inhibitors/agonists.

RESULTS

The analysis identified 321 compounds in CGRG, of which 54 were subjected to network pharmacology analysis; 159 targets and 187 significantly enriched KEGG pathways were recognized, including the MAPK and sphingolipid pathways, which were found to be potential contributors to the anti-fibrotic effects of CGRG. In vivo, CGRG decreased the serum concentrations of ALT, AST, and ALP, along with the production of TNF-α and IL-1β, as well as α-SMA and COL1A1 levels. In vitro, CGRG repressed cell proliferation, migration ability, and TGF-β1-induced activation. The anti-fibrotic effects of CGRG were associated with the suppression of the ERK signaling pathway, which is modulated by the SphK1-S1PR2 axis; the depletion of SphK1 and S1PR2 attenuated downstream p-ERK and α-SMA levels in TGF-β1-stimulated JS-1 cells. Moreover, PF-543 and JTE-013 significantly blocked TGF-β1-induced α-SMA upregulation, thus suppressing CGRG's ability to downregulate α-SMA expression. MHP and CYM5520, intensified TGF-β1-induced p-ERK and α-SMA expression, thus counteracting the inhibitory effects of CGRG on α-SMA expression.

CONCLUSION

CGRG ameliorates LF by inhibiting the SphK1-S1PR2-ERK pathway, offering new mechanistic insights and supporting its clinical application. These findings highlight the value of TCM polypharmacology in targeting redundant fibrogenic pathways.