Gut-Liver Interactions in Metabolic Liver Disorders

The gut and the liver maintain a dynamic, bidirectional relationship that is central to metabolic homeostasis and the pathogenesis of disorders such as non-alcoholic fatty liver disease (NAFLD), metabolic-associated steatotic liver disease (MASLD) and non-alcoholic steatohepatitis (NASH). Nutrients, microbial metabolites and immune mediators travel from the intestine to the liver via the portal circulation, while bile acids and hepatic secretions influence gut barrier integrity and the composition of the microbiota. Disruption of this axis through overnutrition, insulin resistance, dysbiosis or increased intestinal permeability promotes chronic inflammation, lipid accumulation, oxidative stress and fibrogenesis in the liver. Emerging evidence supports a “multiple hit” model in which genetic predisposition, environmental factors and cross-talk between epithelial, immune and parenchymal cells in both organs converge to drive progressive liver injury. Modulating microbial composition, reinforcing barrier function and targeting specific metabolic receptors now represent promising therapeutic strategies.

Research from Nature Portfolio

Recent studies have delineated how microbial metabolites shape hepatic lipid metabolism by engaging nuclear and cell-surface receptors. One investigation demonstrated that altered bile acid transformation by specific gut bacteria modulates the farnesoid X receptor pathway in hepatocytes, reducing steatosis and inflammatory signalling. Another multi-omic analysis identified microbial-derived lipopolysaccharide fragments that activate Toll-like receptor 4 on Kupffer cells, thereby exacerbating fibrotic responses in preclinical models. A third report revealed that strengthening the gut vascular barrier attenuates portal endotoxaemia and halts progression from simple steatosis to steatohepatitis in murine systems, underscoring the therapeutic potential of vascular-targeted interventions.

Gut-Liver Interactions in Metabolic Liver Disorders publication trend

The graph below shows the total number of articles in gut-liver interactions in metabolic liver disorders across all publications each year (not limited to Nature Index journals).

Technical terms

Gut–liver axis: The physiological and biochemical communication network linking intestinal functions with hepatic processes.

Dysbiosis: An imbalance in the composition, diversity or function of the gut microbiota.

Intestinal permeability: The selective barrier property of the gut epithelium that regulates the passage of molecules and microbes.

Farnesoid X receptor (FXR): A nuclear receptor activated by bile acids that controls lipid, glucose and inflammatory pathways in the liver and intestine.

Short-chain fatty acids (SCFAs): Metabolic by-products of microbial fermentation of dietary fibres, involved in energy homeostasis and immune regulation.

Kupffer cells: Liver-resident macrophages that sense microbial products and orchestrate hepatic immune responses.

References

1. Breaking the barriers: the role of gut homeostasis in Metabolic-Associated Steatotic Liver Disease (MASLD). Gut Microbes (2024).
2. The Role of the Gut-Liver Axis in Metabolic Dysfunction-Associated Fatty Liver Disease. Frontiers in Immunology (2021).
3. Liver Steatosis, Gut-Liver Axis, Microbiome and Environmental Factors. A Never-Ending Bidirectional Cross-Talk. Journal of Clinical Medicine (2020).