Excessive release of interleukin-1β (IL-1β) is well-known to provoke cascades of inflammatory responses thus contributing to the pathogenesis of alcohol-induced steatohepatitis (ASH), but the cellular mechanism that regulates IL-1β release during ASH remains unclear. Herein, we identified that gasdermin D (GSDMD) membrane pore is critical in mediating IL-1β hypersecretion from chronic ethanol or acetaldehyde-stimulated macrophages. Deletion of GSDMD reduced IL-1β release and ameliorated alcoholic steatohepatitis in vivo. These findings uncovered a novel mechanism regarding the IL-1β release in ASH, and also indicated the therapeutic potential of IL-1β blockade. Interleukin-1 receptor antagonist (IL-1Ra) is protective to ASH by blocking IL-1β, but it has a short biological half-life (4-6 h) and lower liver concentrations. Thus, we constructed a therapeutic plasmid pVAX1-IL-1Ra-ApoAI (pVAX1-IA) encoding IL-1Ra anchored to the liver-targeting protein apolipoprotein A-I (ApoAI), and developed hepatocyte-specific nanobiologics (Glipo-pVAX1-IA) by galactose functionalization for local and prolonged expression of IL-1Ra in liver. Data presented here showed that Glipo-pVAX1-IA facilitated efficient uptake of gene cargos by hepatocytes. The biodistribution studies confirmed a predominant hepatocytes internalization, but a minimal kupffer cells uptake of Glipo-pVAX1-IA following intravenous injection. The locally secreted IL-1Ra attenuated alcohol-induced steatohepatisis and infiltration of inflammatory cells. Together, our results unraveled the critical role of GSDMD membrane pore in IL-1β hypersecretion and highlighted the hepatocyte-specific Glipo-pVAX1-IA nanobiologics as a promising therapeutic strategy for ASH.
Keywords: Alcohol-induced steatohepatitis; Apolipoprotein A-I; Galactose; Gasdermin D; Interleukin-1 receptor antagonist; Interleukin-1β.
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