Transcriptome and Gut Microbiota Profiling Revealed the Protective Effect of Tibetan Tea on Ulcerative Colitis in Mice

Traditionally, Ya'an Tibetan tea is routinely consumed by local people in the Tibet region. It is believed to possess promising anti-inflammatory benefits. This study was conducted to elucidate the protective impact of Tibetan tea extract (TTE) on dextran sodium sulfate (DSS)-induced colitis in mice. Mice were split into four groups: control (C) group, Tibetan tea (T) group, DSS-induced model (CD) group, and Tibetan tea + DSS (TD) group. The intake of TTE significantly reduced the clinical symptoms of ulcerative colitis (UC) by alleviating the impact of cellular damage and reducing glandular hypertrophy and the infiltration of inflammatory cells. UC led to a prominent shift of the microbial communities in the gut. Interestingly, the beneficial microbes, such as Lactobacillus reuteri, Bifidobacterium choerinum, and Lactobacillus intestinalis, were significantly increased in TTE-treated mice when compared to any other experimental group. The transcriptome analysis revealed that the positive effect of TTE on UC could be attributed to changes in the G alpha (i) signaling pathway and the innate immune system. The genes related to inflammation and immune system pathways were differentially expressed in the TTE-treated group. Moreover, the relative expression of genes linked to the inflammatory TLR4/MyD88/NF-kappa B signaling pathway was significantly downregulated toward the level of normal control samples in the TD group. Overall, this study revealed the modulatory effect by which TTE reversed the development and severity of chronic colon damage.