Water and some foods are important sources of fluoride (F-) exposure, therefore, it is necessary to study intestinal F- absorption and its influencing factors to assess the benefits or risks of F- exposure. Our previous study found that theaflavins including theaflavin (TF), theaflavin-3-gallate (TF3G), theaflavin-3′-gallate (TF3′G) and theaflavin-3,3′-digallate (TFDG) could all significantly inhibit F- transport in Caco-2 monolayer models. However, information on its related mechanisms is still scarce. In this study, its related mechanisms were revealed by network pharmacology integrated transcriptomic analysis. A total of 27 candidate target proteins were screened by network pharmacology analysis for theaflavins inhibiting F- transport. Weighted gene co-expression network analysis (WGCNA) of transcriptome data identified three co-expression modules including 1422 genes. Further, 53 hub genes were screened by protein-protein interaction (PPI) network. Notably, MAPK8 (also called JNK1, c-Jun N-terminal kinase 1) was both a candidate target in network pharmacology analysis and a hub gene in WGCNA. The GO and KEGG results suggested that theaflavins inhibiting F- transport may be related to the MAPK signaling pathway. Further experiment showed that TF could reverse F--mediated activation in the JNK MAPK signaling pathway activation and increase in intracellular reactive oxygen species (ROS). In addition, we demonstrated that TF could restore the F--mediated in decreased expression and disorder of tight junction proteins, which ultimately inhibited F- transport. In conclusion, the inhibition of F- transport in Caco-2 monolayer models by theaflavins may be mediated via the ROS/JNK MAPK/tight junction signaling pathway.
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