EFFECTS OF MELATONIN AND PHYSICAL EXERCISE ON THE ANALYSIS OF THE INTESTINAL MICROBIOTA IN AN EXPERIMENTAL MODEL OF CIRRHOSIS: COMPOSITION, DIVERSITY AND FUNCTIONAL CHANGES

Introduction and Objectives

Changes in the composition of the intestinal microbiota have been associated with several diseases, including cirrhosis. Melatonin has antioxidant and anti-inflammatory properties with protective effects in experimental models. Physical exercise is widely recognized for its systemic benefits.

To evaluate the intestinal microbiota in an experimental model of cirrhosis after treatment with melatonin and physical exercise.

Materials and Methods

Twenty male Wistar rats were divided into groups: CO, BDL, BDL+MLT and BDL+EX. Cirrhosis was induced by bile duct ligation. Melatonin was administered i.p. (20 mg/kg/day) and the exercise protocol consisted of swimming three times a week. After 28 days, fecal samples were collected for microbiota analysis by 16S rRNA gene sequencing. Amplicon sequence variants (ASVs) were identified and alpha diversity (Shannon index), PCA and differential abundance (Log Fold Change) analyses were performed.

Results

A total of 1197 ASVs. The predominant phyla were Firmicutes, Bacteroidetes, Proteobacteria and Actinobacteria, comprising more than 90% of the microbiota. In the BDL+MLT and BDL+EX groups, there was an increase in Blautia and Lachnospiraceae, producers of short-chain fatty acids; Turicibacter, associated with serotonergic signaling and potential protection against intestinal tumors; Eubacterium siraeum, with antiadipogenic effects via inhibition of the PI3K/AKT pathway; and Romboutsia, acting on carbohydrate and bile acid metabolism. In the BDL group, there was a reduction in Firmicutes and an increase in E. ruminantium, a pathogenic species.

Conclusions

The analysis revealed significant changes in the composition of the intestinal microbiota in response to cirrhosis, with beneficial modulation by melatonin and physical exercise.

Conflict of interest: None