The role of bile acid dynamics in inflammatory bowel disease and metabolic dysfunction-associated steatotic liver disease

Abstract

The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) is higher among individuals with inflammatory bowel disease (IBD) than in the general population. Emerging evidence indicates that the development of MASLD in patients with IBD may occur independently of traditional metabolic risk factors, suggesting a unique pathophysiological mechanism distinct from conventional MASLD pathways. Bile acids (BAs), which act as critical signaling molecules in enterohepatic circulation, play an essential role in maintaining gastrointestinal homeostasis through bidirectional gut-“liver axis communication. These molecules are increasingly recognized as pivotal regulators in the progression of both MASLD and IBD. While previous studies have characterized the dynamics of BA in blood or fecal samples under both conditions, a comprehensive understanding of their metabolic profiles and the associated interactions within the gut-liver axis is still lacking. This review synthesizes current evidence from studies employing BA metabolomics to investigate IBD and MASLD. By focusing on BA signatures, we summarize conserved alterations between these two conditions and their potential mechanisms of disease progression. Our review advances understanding of BA-mediated pathways in IBD and MASLD, providing a foundation for assessing their roles in contributing to the pathogenesis of MASLD in patients with IBD.

Keywords

Bile acids (BAs) / Inflammatory bowel disease (IBD) / Metabolic dysfunction-associated steatotic liver disease (MASLD)

Authors’ contributions

Si-Rui Yu: Writing-original draft, Writing-review & editing, Visualization. Run Sun: Writing-original draft, Writing-review & editing. Mei-Ya Shi: Writing-review & editing, Project adminis-tration. Mei Yang: Writing-review & editing, Project administra-tion. Kun Chen: Writing-review & editing, Project administration. Qiong Pan: Writing-review & editing, Project administration. Ling Zhao: Writing-review & editing, Conceptualization. Ming-Yue Wu: Conceptualization, Supervision, Writing-original draft, Writing-review & editing, Visualization, Funding acquisition. Jin Chai: Conceptualization, Supervision, Project administration, Writing-review & editing, Funding acquisition.

Declaration of competing interest

The authors declare that there is no conflicts of interest.

Acknowledgements

This work was supported by Prevention and Control of Emerging and Major Infectious Diseases-National Science and Technology Major Project (No. 2025ZD01906400 to Jin Chai), Na-tional Natural Science Foundation of China (No. 82325008 and 82450104 to Jin Chai), and National Natural Science Foundation of China (No. 82200585 to Ming-Yue Wu).

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