The dissertation explored how gut microbiota responds to exercise and diet and how these shifts may help combat metabolic fatty liver disease.
Findings revealed that physical activity and prebiotic fiber supplementation alter microbial metabolism in ways that support improved metabolic health.

The gut microbiota plays a vital role in human metabolism by breaking down indigestible food and producing metabolites that impact the entire body particularly via the gut-liver axis. Disruptions in this microbial balance are linked to the onset of metabolic-dysfunction associated steatotic liver disease (MASLD).

The dissertation investigated how prebiotics and physical activity enhance microbial diversity and support beneficial strains with microbial metabolites mediating these health effects. It also developed new methods to integrate microbiota profiling with metabolomic analysis.

Exercise and Prebiotics Alter Microbial Chemical Environment

A six-week endurance training program led to notable shifts in gut microbiota composition and systemic metabolism. Notably levels of free phospholipids in the blood and their breakdown products in the gut increased coinciding with a rise in beneficial Akkermansia bacteria. These findings suggest that exercise-induced fat metabolism may support the growth of health-promoting microbial strains.

Dietary supplementation with xylo-oligosaccharide (XOS) fibers significantly reduced liver fat and inflammation in test animals though responses varied among individuals. The intervention notably decreased harmful amino acid metabolites in the gut linked to a reduction in protein-degrading bacterial strains. Individuals who showed the greatest benefit initially had higher levels of these metabolites and an imbalanced ratio between Bacteroides and Faecalibacterium.

Metabolic syndrome and its related condition fatty liver disease pose significant global health challenges, with no universally effective medication currently available. This study reinforces the growing evidence that a combination of targeted dietary interventions and regular physical activity can positively influence liver health by modulating the gut microbiota. The findings offer valuable insights for designing new personalized strategies that integrate nutrition and exercise to improve metabolic outcomes through the gut-liver axis.

The public examination of Jukka Hintikka’s doctoral dissertation titled Associations of Microbial Metabolism with Metabolic Health and Physical Activity – The Gut-Liver Axis in the Focus of Metabolomes and Microbiomes presents a comprehensive investigation into how microbial metabolism connects lifestyle factors with liver and overall metabolic health. The research bridges microbiome science and metabolomics paving the way for innovative approaches in disease prevention and management.

Source: https://www.jyu.fi/en/news/exercise-and-dietary-fiber-shape-gut-microbiota-supporting-liver-and-whole-body-health