Punicalagin Alleviates Acute Liver Injury via Dual STAT1 / NF ‐ κB Inhibition and STAT3 Activation to Orchestrate M1‐to‐M2 Macrophage Polarization

ABSTRACT Acute liver injury (ALI) is characterized by excessive inflammation and macrophage polarization, with the M1‐to‐M2 phenotypic shift emerging as a critical regulatory node. Punicalagin (PUN), a polyphenolic compound derived from pomegranate, has demonstrated hepatoprotective effects in preclinical models; however, its molecular mechanisms underlying macrophage polarization and inflammatory signaling remain unclear. This study aims to investigate the role of PUN in modulating macrophage polarization and inflammatory pathways in chemical‐ and drug‐induced ALI. CCL 4 ‐ and APAP‐induced ALI mouse models were employed to assess the hepatoprotective effects of PUN through liver enzyme analysis, histology, and immune phenotyping. In vitro, LPS‐stimulated RAW264.7 macrophages were treated with PUN, and mechanisms were examined through western blotting, qRT‐PCR, flow cytometry, and ELISA. PUN (12.5 mg kg −1 ) significantly reduced serum levels of ALT and AST, as well as the necrotic area in both ALI models. It reduced hepatic infiltration of monocyte‐derived macrophages (MDMs) and lowered the expression of M1 markers (CD86, iNOS), while simultaneously increasing the expression of M2 markers (CD206, Arg‐1). Mechanistically, PUN inhibited the phosphorylation of NF‐κB and STAT1, while promoting the activation of STAT3, which resulted in a reduction of TNF‐α and IL‐6 levels (approximately 62%–71%), alongside an increase in IL‐10 and TGF‐β, both in vivo and in vitro. Similar reprogramming from M1 to M2 and cytokine shifts were observed in LPS‐challenged RAW264.7 cells. PUN alleviates ALI by promoting M1‐to‐M2 macrophage polarization through the dual inhibition of NF‐κB/STAT1 and the activation of STAT3. These findings underscore PUN as a potential therapeutic agent for ALI by reprogramming the hepatic immune microenvironment.