Dishevelled 2 (Dvl2) is a key mediator of the Wingless/Wnt signaling pathway that regulates cell proliferation, migration, and immune function. However, little is known about the role of macrophage Dvl2 in modulating NOD1-mediated pyroptosis and hepatocyte death in oxidative stress-induced inflammatory liver injury. In a mouse model of oxidative stress-induced liver inflammation, mice with myeloid-specific Dvl2 knockout (Dvl2M-KO) displayed exacerbated ischemia/reperfusion (IR) stress-induced hepatocellular damage with increased serum ALT levels, oxidative stress, and proinflammatory mediators. Unlike in Dvl2FL/FL controls, Dvl2M-KO enhanced NOD1, caspase-1, GSDMD, and NF-κB activation in liver macrophages after IR. Interestingly, IR stress enhanced YAP colocalized with HSF1 in Dvl2FL/FL macrophages, while macrophage Dvl2 deficiency reduced YAP and HSF1 colocalization in the nucleus under inflammatory conditions. Importantly, Dvl2 deletion diminished nuclear YAP interacted with HSF1 and augmented NOD1/caspase-1 and GSDMD activation in response to inflammatory stimulation. However, Dvl2 activation increased YAP interaction with HSF1 and activated HSF1 target gene eEF2, inhibiting NOD1/caspase-1, GSDMD, and NF-κB activity. Moreover, macrophage eEF2 deletion increased the NOD1-caspase-1 interaction, GSDMD activation, HMGB1 release, and hepatocyte LDH release after macrophage/hepatocyte co-culture. Adoptive transfer of eEF2-expressing macrophages in Dvl2M-KO mice alleviated IR-triggered liver inflammation and hepatocellular damage. Therefore, macrophage Dvl2 deficiency promotes NOD1-mediated pyroptosis and exacerbates IR-induced hepatocellular death by disrupting the YAP-HSF1 axis. eEF2 is crucial for modulating NOD1-driven pyroptosis, inflammatory response, and hepatocyte death. Our findings underscore a novel role of macrophage Dvl2 in modulating liver inflammatory injury and imply the therapeutic potential in organ IRI and transplant recipients.
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