Total flavonoid of vine tea reduces neutrophil extracellular traps release by inhibiting PI3K-AKT-mTOR signaling pathway to treat ulcerative colitis

Background: Vine tea, derived from selenium-rich regions of China, has been shown through systematic pharmacological approaches to potentially exhibit significantly superior anti-inflammatory effects in dextran sodium sulfate-induced colitis. However, the mechanism of action is still unclear. Materials and methods: This study analyzed the total flavonoid fraction of Vine tea (VTF) using untargeted metabolomics with UHPLC-OE-MS mass spectrometry. The chemical composition of the VTF samples was characterized through a comprehensive review of literature reports and relevant databases for network pharmacology. We constructed a visualization network linking VTF, compounds, pathways, and ulcerative colitis using GO and KEGG analyses. To evaluate the therapeutic effects of VTF on UC, we established a mouse model of ulcerative colitis induced by 3 % dextran sodium sulfate and assessed the effects of VTF treatment. Additionally, a cellular model was developed, and the Cell Counting Kit-8 assay was used to determine the optimal dosing concentration of VTF in neutrophils. Laser confocal microscopy was employed to analyze the co-localization of P62-LC3 and the expression of Citronelated Histone H3 following VTF intervention. Results: This study identified the five main components of total flavonoids in Vine tea using UHPLC-OE-MS non-targeted metabolomics. We explored the potential mechanisms of VTF intervention in ulcerative colitis using network pharmacology. This analysis identified 112 linker genes. The GO and KEGG enrichment analyses suggested that the inhibitory effect of VTF on intestinal inflammation might be related to the PI3K-AKT-mTOR signaling pathway. In vivo experimental validation revealed that VTF significantly increased colon length and decreased the Disease Activity Index score ( P < 0.05). VTF also reduced serum levels of inflammatory factors TNF-α and IL-1β ( P < 0.05), improved colon histopathology, and restored the levels of intestinal tight junction proteins Occludin and Zonula Occludens-1. These findings suggest that VTF can ameliorate ulcerative colitis in the colon of mice. In vitro , VTF upregulated cellular macroautophagy through the PI3K-AKT-mTOR signaling pathway and inhibited the release of Neutrophil Extracellular Traps. However, In vitro experiments revealed no direct relationship between autophagy and Neutrophil Extracellular Traps under VTF intervention. Conclusion: The mechanism by which VTF ameliorate Dextran Sodium Sulfate-induced ulcerative colitis in mice may involve promoting autophagy through downregulation of the PI3K-AKT-mTOR signaling pathway, reducing the release of Neutrophil Extracellular Traps, and restoring the intestinal barrier. However, no direct relationship was observed between the autophagy induced by VTF intervention and the release of Neutrophil Extracellular Traps. • Vine tea's anti-inflammatory potential. • Cost-effective UC treatment. • Autophagy-NETs interaction.