Metabolic dysfunction-associated steatohepatitis (MASH) is a progressive liver disease linked to fibrosis and hepatocellular carcinoma (HCC). Gut-derived lipopolysaccharide (LPS) promotes hepatic inflammation, fibrosis, and angiogenesis through toll-like receptor 4 (TLR4) signaling. This study examined the effects of rifaximin, a non-absorbable, gut-targeted antibiotic, on MASH-related liver fibrosis and early hepatocarcinogenesis, with a focus on the LPS–epiregulin–IL-8–angiogenesis axis.MASH was induced in Fischer 344 rats using a choline-deficient, L-amino acid-defined high-fat diet (CDAHFD). Rifaximin (30 mg/kg/day) was orally administered for 12 weeks. Liver histology, gene expression, intestinal permeability, LPS levels, and angiogenic markers were evaluated. Rifaximin reduced hepatic inflammation, fibrosis, hydroxyproline content, and fibrogenic gene expression. The number and size of GST-P-positive preneoplastic lesions and proliferation-related genes were decreased. Portal LPS levels and Kupffer cell activation declined, with downregulation of Lbp, Cd14, Tlr4, and inflammatory cytokines. Rifaximin decreased hepatic epiregulin and IL-8 expression, attenuated CD34-positive neovascularization, and suppressed proangiogenic gene expression, accompanied by improved intestinal barrier function and reduced gut permeability. Rifaximin mitigates MASH progression by restoring gut barrier integrity, limiting LPS translocation, and inhibiting fibrogenic and angiogenic pathways. These results suggest its potential as a chemopreventive agent in MASH-related hepatocarcinogenesis.

Gut barrier dysfunction and portal endotoxemia contribute to metabolic dysfunction-associated steatohepatitis (MASH) progression through activation of hepatic inflammatory signaling. Milk-derived extracellular vesicles (EVs) contain bioactive microRNAs and have recently attracted attention as modulators of intestinal homeostasis. This study investigated the effect of bovine milk-derived extracellular vesicles (B-mEVs) in ameliorating MASH by improving intestinal barrier function. C57BL/6J mice fed a choline-deficient amino acid-defined high-fat diet (CDA-HFD) were orally treated with B-mEVs, and therapeutic effects were evaluated. Liver histology, fibrosis, portal lipopolysaccharide (LPS) levels, intestinal permeability, and gut microbiota composition were evaluated. The direct effects of B-mEVs on intestinal barrier function were assessed using palmitic acid-stimulated Caco-2 cells. Small RNA sequencing and microRNA enrichment analyses were performed to characterize B-mEV cargo. B-mEV treatment attenuated hepatic steatosis, inflammation, and fibrosis in CDA-HFD-fed mice and reduced serum aminotransferase levels, portal LPS concentrations, hepatic macrophage accumulation, and hepatic TLR4/NF-κB signaling activation. Meanwhile, B-mEVs restored intestinal tight junction proteins, including ZO-1, occludin, and claudin-1, and improved intestinal permeability in vivo. In Caco-2 cells, B-mEVs attenuated palmitic acid-induced barrier dysfunction and suppressed myosin light chain kinase expression. Gut microbiota analysis revealed partial restoration of Akkermansia abundance after B-mEV administration. Furthermore, to explore the molecular basis of these protective effects, small RNA sequencing demonstrated enrichment of regulatory microRNAs, including let-7a-5p, and pathway analyses identified associations with intestinal barrier and inflammatory signaling pathways. B-mEVs ameliorated CDA-HFD-induced steatohepatitis by restoring intestinal barrier integrity and suppressing gut-derived LPS/TLR4 inflammatory signaling. These findings suggested that milk EVs may represent a novel gut–liver axis-targeted therapeutic strategy for MASH.

Objectives: Metabolic dysfunction-associated steatohepatitis (MASH) is a leading cause of cirrhosis within the spectrum of metabolic dysfunction-associated steatotic liver disease (MASLD). However, the prognostic impact of diabetes mellitus (DM) in MASH-associated cirrhosis remains unclear. This study aimed to compare clinical outcomes between cirrhotic patients with and without DM. Methods: Patients with MASH-related cirrhosis were stratified into DM (DM-MASH) and non-DM (non-DM MASH) groups. The diagnosis of MASH was based on histological evidence of steatohepatitis with underlying metabolic dysfunction. The non-DM group included both obese individuals and lean/normal-weight individuals with ≥1 metabolic risk factors. Mortality, liver-related events (LREs; ascites, variceal bleeding, encephalopathy, and hepatocellular carcinoma), and sarcopenia were compared using Kaplan–Meier analysis, log-rank tests, and Fisher’s exact test. Risk factors for sarcopenia were assessed using logistic regression. Results: Median survival was significantly shorter in DM-MASH patients compared to non-DM MASH patients (1523 vs. 2618 days; p < 0.05). The incidence of LREs during follow-up was also higher in the DM-MASH group. The prevalence of sarcopenia was significantly greater among DM-MASH patients (36.1% vs. 19.7%; p < 0.05). In multivariate analysis, DM emerged as an independent predictor of sarcopenia in patients with MASH-related cirrhosis. Conclusions: DM is associated with worse outcomes in MASH-driven cirrhosis, including increased sarcopenia and reduced survival. DM may serve as a prognostic marker for identifying high-risk patients with MASH-associated cirrhosis.