Gut bacterial bile salt hydrolase as a promising therapeutic target in certain internal diseases. Literature review

Bile acids (BA) are essential compounds synthesized in the liver from cholesterol and considered as signaling molecules, influencing a number of receptors and metabolic processes forming an axis «bile acids‑gut‑microbiome‑liver». Bacterial bile salt hydrolase (BSH) activity is essential for the regulation of BA metabolism, and its expression varies across different gut bacterial species. Imbalances in gut microbiota and reduced BSH activity are associated with various disorders, including obesity, metabolic syndrome, inflammatory and functional bowel diseases. Recent studies highlight a bidirectional relationship between BAs, gut microbiota, and metabolic health, with altered BA metabolism being implicated in conditions such as dyslipidemia, cardiovascular diseases, and gastrointestinal disorders. Probiotics, particularly BSH‑expressing strains, show promising potential in modulating BA metabolism, improving lipid profiles, mitigating cardiovascular risk and BA malabsorption. Clinical trials suggest that these probiotics may lower cholesterol, with associated improvements in cardiovascular risk. Additionally, probiotic treatment with BSH‑expressing strains has demonstrated benefits in functional gastrointestinal disorders like irritable bowel syndrome, where BSH activity is reduced, and BA malabsorption is present. However, further research is required to confirm the therapeutic potential of BSH‑expressing probiotics for managing dyslipidemia, cardiovascular risk, and gastrointestinal disorders. In conclusion, BAs and their microbial transformations play a crucial role in maintaining metabolic and gastrointestinal health. BSH‑expressing probiotics may offer a novel approach to modulate BA metabolism and alleviate related disorders, though further clinical studies are necessary to substantiate their clinical utility and inclusion in therapeutic guidelines.