Gut-liver axis

The gut-liver axis refers to the bidirectional relationship between the gastrointestinal tract, its resident microbiota, and the liver, connected primarily via the portal vein (Albillos et al., 2020). This axis is fundamental for maintaining metabolic homeostasis and immune regulation, as the liver receives approximately 70% of its blood supply from the intestine, exposing it to gut-derived nutrients and microbial products (Milosevic et al., 2019). In healthy individuals, a robust intestinal barrier prevents the translocation of harmful bacteria and pathogen-associated molecular patterns (PAMPs) like lipopolysaccharides. However, dysbiosis or increased intestinal permeability—often termed leaky gut—allows these inflammatory mediators to reach the liver, where they activate Toll-like receptors and promote chronic inflammation (Tilg et al., 2016). This process is a key driver in the pathogenesis of diseases such as non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), and cirrhosis. Therapeutic interventions targeting this axis include farnesoid X receptor (FXR) agonists like obeticholic acid, which regulate bile acid flow, and non-absorbable antibiotics like rifaximin, which reduce the load of ammonia-producing bacteria. Emerging strategies also explore the use of probiotics and fecal microbiota transplantation to restore a healthy gut environment and mitigate liver injury.

Other names

Enterohepatic axisGut-liver communicationIntestinal-liver axis

Modulation of the bidirectional communication between the gut and liver by targeting bile acid receptors (FXR/TGR5), reducing intestinal permeability, and altering gut microbiota composition to decrease systemic inflammation.