Abstract
Background: Hemolytic jaundice, characterized by excessive bilirubin production and hepatic dysfunction, currently lacks effective therapeutic strategies targeting its underlying mechanisms. Methods: This study evaluated the therapeutic potential of the aqueous extract of Inonotus obliquus (IO) in ameliorating hemolytic jaundice through modulation of the gut–liver axis. A murine model of hemolytic jaundice was induced by phenylhydrazine (PHZ) administration, and IO was orally administered as the intervention. Antibiotic depletion and FMT verified gut microbiota dependence. Liver injury, serum bilirubin, gut microbiome, and metabolites were assessed. Results: IO treatment significantly alleviated PHZ-induced hemolytic jaundice in mice. Notably, antibiotic-mediated depletion of the gut microbiota abolished the hepatoprotective effects of IO, whereas fecal microbiota transplantation (FMT) from IO-treated donors conferred marked amelioration of hyperbilirubinemia in recipient mice. Integrative multi-omics analysis identified Limosilactobacillus reuteri and Lactobacillus johnsonii as the predominant microbial species altered by IO. Furthermore, IO upregulated the expression of farnesoid X receptor (FXR) and pregnane X receptor (PXR) in both hepatic and intestinal tissues and also increased the expression of bile salt export pump (BSEP) and multidrug resistance-associated protein 2 (MRP2). These alterations were correlated with an increased excretion of bile acids and bilirubin into the intestinal lumen, thereby mitigating hepatic injury. This process may be associated with the modulation of gut microbiota. Conclusions: These findings collectively provide evidence of a significant correlation between IO treatment and the mitigation of hemolytic jaundice, achieved by modulating the enterohepatic circulation of bile acids and bilirubin through the regulation of gut microbiota. Our results highlight the potential of IO as a microbiota-directed nutritional strategy for the management of jaundice.