Extracellular vesicles from immortalised human amniotic epithelial cells reduce hepatic fibrosis in mice with Steatohepatitis and Hepatocellular Carcinoma

Background Metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction-associated steatohepatitis (MASH) and cirrhosis and hepatocellular carcinoma (HCC) describe progressive stages of liver disease that occurs secondary to inflammation driven by abnormal hepatic lipid accumulation. Treatment that addresses the pathophysiology that underlies MASH/HCC progression is currently lacking. Human amniotic epithelial cell derived EVs (hAEC-EVs) demonstrate anti-inflammatory, anti-fibrotic and reparative properties. Methods We aimed to investigate the therapeutic efficacy of immortalised hAEC-EVs (ihAEC-EVs) in a murine model of MASH and HCC and characterize both protein and miRNA cargo to explain therapeutic mechanisms. MASH and HCC was induced in mice following a ‘western diet’ and carbon tetrachloride (CCl ₄ ) exposure for 12 weeks or 24 weeks respectively. 10µg of ihAEC EVs (treatment) and 10mg/kg obeticholic acid (treatment benchmark) was administered via oral gavage. Serum was collected for metabolic parameter analysis and livers were collected for histological and molecular analysis. Results Oral administration of ihAEC-derived extracellular vesicles (EVs) significantly reduced liver fibrosis and inflammation in MASH by reducing hepatic stellate cells and macrophages. These findings are supported by protein and miRNA analysis that reveals presence of EV cargo that modulates pathways linked to hepatic inflammation, fibrosis, and LPC response. Conclusions These findings indicate that oral administration of ihAEC-EVs is a promising cell-free therapy for the treatment of MASLD and MASH, having a significant impact on the treatment possibilities for patient's suffering from chronic liver disease. Further, this study allowed us to deduce and validate pathways involved in MASH progression and identify candidate proteins and miRNAs to focus on for future mechanism of action experiments.