Impact of continuous probiotic supplementation on intestinal barrier function and hepatic biomarkers in fulminant liver failure models

Background Fulminant liver failure (FLF) is characterized by sudden hepatocellular necrosis, severe systemic inflammation, and rapid progression to multiorgan failure. Increasing evidence implicates intestinal barrier dysfunction and microbe-associated molecular pattern (MAMP) translocation as key drivers of hepatic injury through gut–liver axis dysregulation. Probiotic-mediated modulation of epithelial integrity and mucosal immunity has shown promise; however, available data in FLF settings remain limited. Objectives This study examined whether continuous probiotic supplementation modulates intestinal epithelial barrier function, limits bacterial translocation, and reduces biochemical and histopathological indicators of hepatic damage in d -galactosamine/lipopolysaccharide (GalN/LPS)-induced FLF models. Methods Male Wistar rats were randomized into three groups: (i) healthy controls, (ii) FLF (700 mg/kg GalN + 10 µg/kg LPS, intraperitoneal), and (iii) FLF + probiotics. Animals in the probiotic group received a multistrain probiotic formulation ( Lactobacillus rhamnosus GG, Lactobacillus plantarum , Bifidobacterium longum ) at 10 9 CFU/day orally for 14 days prior to FLF induction and continued until they were killed. Intestinal permeability was measured using serum FITC-dextran translocation. Tight junction protein profiles (ZO-1, occludin, claudin-1) were evaluated using Western blotting and confocal immunofluorescence. Hepatic damage was assessed by serum Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), total bilirubin, alkaline phosphatase, and oxidative stress markers (MDA, GSH). Systemic irritation was characterized by measuring tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β, and IL-6 using enzyme-linked immunosorbent assay (ELISA). Liver tissues were inspected for necroinflammatory changes utilizing H&E scoring and TUNEL assay. Results Probiotic supplementation markedly reduced GalN/LPS-induced intestinal hyperpermeability ( p < 0.01) and protected tight junction architecture, as demonstrated by restored ZO-1 and occludin localization and increased claudin-1 expression. Treated animals exhibited notably significant increases in ALT, AST, bilirubin, ammonia, and oxidative stress markers (all p < 0.05). Cytokine profiling showed significant decreases in TNF-α, IL-1β, and IL-6 levels compared with untreated FLF animals. Histopathological analysis revealed reduced hepatocellular damage, decreased apoptotic cell burden, and lower composite liver injury scores in the probiotic group. Conclusion Continuous probiotic administration provides critical protection against FLF by fortifying epithelial tight junction integrity, suppressing gut-derived inflammatory signaling, and limiting hepatocellular damage. These findings support the utility of targeted microbiota-directed interventions as adjunctive preclinical therapeutic strategies for acute liver failure and warrant further translational evaluation.