Ecliptasaponin A alleviates inflammation and fibrosis in experimental MASH mice via targeting the NLRP3 inflammasome and YAP signaling pathway.

[BACKGROUND] Metabolic dysfunction-associated steatohepatitis (MASH) has emerged as the primary contributor to the increasing incidence and mortality rates linked to cirrhosis and hepatocellular carcinoma globally, while the availability of clinical treatment drugs remains severely limited. Ecliptasaponin A (EA), naturally isolated from Ecliptae Herba, possesses multiple biological activities. However, the effects of EA on MASH remain unclear.

[PURPOSE] This study aimed to explore the roles of EA in MASH and its engaged mechanisms.

[METHODS] Two established NASH animal models, non-obese MASH induced by methionine-choline-deficient (MCD) dietary administration and obese MASH developed through high-fat/high-cholesterol (HFHC) feeding were employed to assess EA's therapeutic effects in vivo. RNA-seq analysis was conducted to uncover EA's molecular mechanisms. Complementary in vitro investigations utilized LPS-treated BMDMs and THP1 cells, and TGF-β1-activated LX-2 hepatic stellate cells to systematically examine EA's cellular-level impacts and regulatory pathways.

[RESULTS] Oral administration of EA demonstrated dose-responsive therapeutic effects against MCD/HFHC-induced MASH. The compound effectively attenuated hepatic steatosis, inflammatory responses, and fibrotic progression in experimental models through dual modulation of NLRP3 and YAP signaling pathways. Mechanistic studies revealed EA specifically suppressed NLRP3 inflammasome activation in BMDMs without affecting AIM2 or NLRC4 inflammasomes, effectively blocking cytokine secretion, pyroptotic cell death, caspase-1 activation, and inflammasome complex formation. Molecular interactions analysis confirmed EA directly binds to NLRP3, disrupting inflammasome assembly. In LX-2 cells, EA suppressed TGF-β1-induced COL1A1 and α-SMA expression while reducing YAP protein levels. Genetic silencing or pharmacological inhibition of YAP failed to potentiate EA's anti-fibrotic effects on α-SMA suppression, Collagen I expression, or YAP-regulated gene transcription. Molecular docking and SPR showed that EZ could directly bind to NLRP3 and YAP.

[CONCLUSION] These findings reveal novel perspectives on the natural compound Ecliptasaponin A, demonstrating its dual-targeting capability against both NLRP3 inflammasome activation and YAP signaling cascades. This discovery highlights its potential as a promising therapeutic agent for mitigating MASH.