Arctigenin Prevents Metabolic Dysfunction-associated Steatohepatitis by Inhibiting NLRP3/GSDMD-N Axis in Macrophages.

Background and Aims: Metabolic dysfunction-associated steatohepatitis (MASH) represents a critical step in the progression from simple fatty liver disease to more severe conditions such as cirrhosis and hepatocellular carcinoma, and it remains difficult to treat. Arctigenin (ATG), a monomer of Fructus Arctii, exhibits anti-inflammatory activity. Therefore, we aimed to examine its potential protective role against MASH and explore the underlying mechanisms. Methods: Male C57BL/6 mice were divided into four groups: control, MASH, low-dose ATG (30 mg/kg/day), and high-dose ATG (120 mg/kg/day). MASH was induced through a choline-deficient, L-amino acid-defined high-fat diet for eight weeks, with concurrent preventive ATG administration. Liver injury, lipid metabolism, inflammation, oxidative stress, and fibrosis were assessed. Network pharmacology was employed to identify the potential protective mechanisms of ATG. Key factors were evaluated in vitro to verify the ATG targets. Results: ATG administration prevented the progression of MASH in a dose-dependent manner. High-dose ATG significantly reduced hepatic macrophage and neutrophil infiltration, serum enzyme levels, and lipid peroxidation, while enhancing antioxidant enzyme activity. Mechanistic network pharmacology identified modulation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome as the central pathway underlying ATG's bioactivity. Functional analyses in lipopolysaccharide-stimulated RAW264.7 cells confirmed that ATG inhibited NLRP3 expression, pyroptosis-related protein cleavage (hereinafter referred to as GSDMD-N), and pro-inflammatory chemokine production in a concentration-dependent manner. Notably, ATG disrupted NLRP3/GSDMD-N axis activity in macrophages without causing cellular toxicity. Conclusions: ATG may inhibit the inflammatory cascade primarily by targeting macrophage NLRP3 inflammasomes, thereby preventing the progression of MASH.