Fecal metabolomic analysis of the role of gut microbiota and short-chain fatty acids in the therapeutic mechanism of Timosaponin AIII in Sjögren's syndrome

Introduction/objectives: Sjogren's syndrome (SS) is a chronic inflammatory and difficult-to-treat autoimmune disease. Timosaponin AIII (TAIII), a plant-derived steroidal saponin, effectively inhibits cell proliferation, induces apoptosis, and exhibits anti-inflammatory properties. This study explored the mechanisms of action of TAIII in SS treatment by studying gut microbiota and short-chain fatty acids (SCFAs) using fecal metabolomics.

Methods: The model group used non-obese diabetic (NOD) mice. The treatment group was classified into TAIII and hydroxychloroquine groups. The gut microbiota, SCFAs, and metabolites were analyzed using 16S rRNA sequencing, gas chromatography-mass spectrometry analysis, and liquid chromatography-mass spectrometry, respectively.

Results: TAIII effectively alleviated dry mouth in NOD mice, slowed the progression of salivary gland tissue injury, reduced inflammatory factor expression, and increased the levels of aquaporins 1 and 5. TAIII regulated SCFA content and tryptophan metabolism by altering the abundance of the Rikenellaceae_RC9_gut_group, thereby reducing the inflammatory response. TAIII can improve imbalances in the gut microbiota and the metabolic levels of related SCFAs and tryptophan, thereby reducing the level of inflammation.

Conclusion: The significant differences observed in the abundance of the Rikenellaceae_RC9_gut_group between the treatment and control groups indicated the potential relationship between bacteria and metabolites in SS. Key Points • The safe and effective treatment of SS with traditional Chinese medicine • Multi-means study on intestinal flora, short-chain fatty acids, and metabonomics.