# Understanding the role of ursodeoxycholic acid and gut microbiome in non-alcoholic fatty liver disease: current evidence and perspectives

## TL;DR

This paper reviews how gut bacteria and ursodeoxycholic acid may help treat non-alcoholic fatty liver disease.

## Contribution

It highlights new insights into the microbiome-UDCA interaction and its therapeutic potential in NAFLD.

## Key findings

- NAFLD patients show distinct gut microbiome signatures with increased Gram-negative bacteria and Prevotella.
- UDCA improves liver health by targeting FXR and other receptors, affecting autophagy and mitochondrial functions.

## Abstract

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, resulting in a huge medical burden worldwide. Accumulating evidence suggests that the gut microbiome and bile acids play pivotal roles during the development of NAFLD. Patients with NAFLD exhibit unique signatures of the intestinal microbiome marked by the priority of Gram-negative bacteria, decreased ratio of Firmicutes/Bacteroidetes (F/B), and increased Prevotella and Lachnospiraceae. The intestinal microbiota is involved in the metabolism of bile acids. Ursodeoxycholic acid (UDCA) is a key determinant in maintaining the dynamic communication between the host and gut microbiota. It generally shows surprising therapeutic potential in NAFLD with several mechanisms, such as improving cellular autophagy, apoptosis, and mitochondrial functions. This action is based on its direct or indirect effect, targeting the farnesoid X receptor (FXR) and various other nuclear receptors. This review aims to discuss the current studies on the involvement of the microbiome–UDCA interface in NAFLD therapy and provide prospective insights into future preventative and therapeutic approaches for NAFLD.