Calycosin limits hepatic fibrogenesis via KLF15 dependent repression of P2X7R in thioacetamide-induced hepatic fibrosis

Ethnopharmacological relevance

Astragalus membranaceus (Fisch.) Bunge is a traditional Chinese medicinal herb that has been documented for its hepatoprotective properties and therapeutic potential. Calycosin, derived from Astragalus membranaceus (Fisch.) Bunge is a natural flavonoid widely used in ameliorating chronic liver diseases.

Aim of the study

The current study investigates hepatoprotective effects as well as the underlying mechanism of Calycosin on hepatic fibrosis.

Materials and methods

Hepatic fibrosis was induced in mice (n = 6) by intraperitoneal injection of thioacetamide (TAA). Subsequently, we deduced the hepatic fibrosis signaling network using RNA sequencing. LX-2 and mouse primary hepatocytes were transfected with the siRNA-KLF15; mouse bone marrow-derived macrophages (BMDMs) were also treated with LPS/ATP and Calycosin to produce conditioned medium. Dual luciferase assay characterized KLF15-P2X7r promoter interaction.

Results

RNA sequencing showed that the KLF15/NOD-like receptor pathway played a significant role in the Calycosin-mediated hepatoprotection in TAA-induced mouse models. Calycosin treatment resulted in a 33 % reduction in ALT and a 35 % decrease in AST levels. In TAA-induced mouse models of hepatic fibrosis, Calycosin greatly diminished the formation of neutrophil extracellular traps. Calycosin treatment induced KLF15 upregulation and a 3-fold reduction in P2X7R protein expression. In the hepatocyte and LX-2, KLF15 deletion cancels the inhibitory effect of Calycosin on the P2X7r. It is shown that KLF15 directly binds to the P2X7r promoter. Furthermore, Calycosin blocked pyroptosis in BMDMs, especially via Calycosin interaction with HSCs-macrophage crosstalk.

Conclusions

This study implies that Calycosin alleviates hepatic fibrosis in the fibroinflammatory lesion through modulating the KLF15-P2X7r/NLRP3 signaling pathway.