Abstract:

The gut microbiota is a complex network of microorganisms inhabiting the gastrointestinal tract and it has a great influence on intestinal health. Disbalances within metabolic patterns and microbial diversity may cause inflammatory bowel disease and other diseases. Microorganisms in intestinal mucosa produce metabolites that act as signalling molecules and influence the regulation of inflammation and the immune response. SCFAs and secondary bile acids are metabolites that bind to specific receptors and trigger inflammatory signals that affect intestinal immunity and host health. Moreover, metabolites of tryptophan promote the integrity of the epithelial barrier and also interact with intestinal mucosal aromatic hydrocarbon receptors (AHR) to regulate immune homeostasis. By acting as precursors to AHR ligands together with SCFAs and secondary bile acids, dietary-derived indoles relax the intestinal epithelium inflammation and stress. The mechanistic and therapeutic advances in non-alcoholic fatty liver disease (NAFLD) aim to alter host metabolism, reduce inflammation, and reconstitute the integrity of the gut barrier through changes in the composition of gut microbiota. Since dysbiosis in liver cirrhosis leads to complications such as bacteremia and hepatic encephalopathy, probiotics and synbiotics are being investigated to treat associated metabolic disorders.

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