[Regulation of Toll-like receptors and their downstream factors by butyrate].

Butyrate, normally produced by probiotics in the gut, not only provides energy for cells, but also changes the phosphorylation, acetylation and methylation levels of many proteins in cells. As a result, it affects the expression of many genes and the transmission of cell signals. Through G protein-coupled receptors, butyrate promotes the secretion of intestinal mucus and the formation of epithelial barriers, and attenuates the impacts of the pathogenic bacteria and their metabolites on human body. The Toll-like receptors (TLRs) are a group of pattern recognition receptors, and their activation causes the translocation of nuclear factor κB (NF-κB) from the cytoplasm to the nucleus and eventually leads to expression and secretion of various pro-inflammatory factors and chemokines. The expression of TLRs is also involved in the pathogenesis of some inflammatory diseases and tumors. The purpose of this review is to summarize the effects of butyrate on TLRs and their downstream signaling pathways. We not only summarized the production of butyrate, the expression of TLRs and the influence of their interaction on the body under the conditions of inflammation and tumor, but also discussed the potential role of butyrate as a bacterial metabolite in the treatments of some human diseases.