NEW research has found that certain bacteria normally found in the mouth can travel to the gut and damage the gut barrier, potentially accelerating chronic liver disease progression.
Mouth-gut-liver axis uncovered
Chronic liver diseases such as metabolic dysfunction-associated steatotic liver disease (MASLD) and its inflammatory form are major global health challenges. While diet, metabolic factors, and alcohol use are known contributors, researchers have increasingly investigated the role of the gut microbiome in liver health.
In the new study, scientists co-led by researchers at King’s College London and partners in Europe identified specific oral bacteria that can translocate to the gut. Once there, these microbes appeared to compromise the integrity of the intestinal barrier – a first line of defence against bacterial products entering the bloodstream.
When the gut barrier is weakened, bacterial products can reach the liver via the portal circulation, triggering inflammation and promoting the development of liver fibrosis, the hallmark of progressive chronic liver disease.
Key findings and implications
The researchers demonstrated in experimental models that oral bacteria associated with periodontal disease were able to accelerate liver scarring by disrupting the gut barrier. This process was linked to increased hepatic inflammation, immune activation, and extracellular matrix deposition – key features of fibrosis progression.
These findings suggest that the mouth-gut-liver axis may be an underappreciated pathway in liver disease pathogenesis. If validated in humans, they could have implications for prevention and management strategies focused on oral health and microbiome modulation.
Clinical relevance
Liver fibrosis progression is a critical determinant of outcomes in chronic liver disease and a key target for surveillance and intervention. A better understanding of contributing factors, including microbial influences, could enhance risk stratification and open avenues for novel preventative approaches.
Clinicians noted that periodontal disease is common and often coexists with metabolic risk factors such as diabetes and obesity, which themselves are major contributors to liver disease risk. Addressing oral health may therefore offer additional benefits in comprehensive liver disease care.
Future research
The authors highlighted the need to investigate whether similar bacterial translocation occurs in humans and how specific microbial species contribute to liver disease progression in different patient populations. Longitudinal clinical studies will be important to confirm whether interventions targeting the oral microbiome or gut barrier integrity can reduce liver fibrosis risk or slow disease progression.
The discovery underscores the complex interplay between microbiomes at different body sites and chronic organ disease, and may refine our understanding of liver disease beyond traditional metabolic and inflammatory paradigms.
Reference
Jin S. Microbial collagenase activity is linked to oral–gut translocation in advanced chronic liver disease. Nat Microbiol. 2026;DOI;10.1038/s41564-025-02223-0.
