Chimonanthus nitens Oliv. Leaf Flavonoids Exert Anti-Inflammatory Effects Through TLR4 Receptor Affecting NF-κB/MAPK Signaling Pathway

Chimonanthus nitens Oliv. leaves (COL), a commonly used traditional Chinese medicine, are rich in a variety of bioactive components, with flavonoids being one of the most abundant. In the current study, RAW264.7 macrophages were induced by lipopolysaccharide (LPS) and treated with COL flavonoids (COLFs). The results demonstrated that COLFs could inhibit the release of nitric oxide (NO) and related inflammatory factors in macrophages. RNA sequencing (RNA-seq) analysis revealed 627 differentially expressed genes (DEGs) in the COLF group, which were further analyzed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. We found that genes involved in biological processes in the LPS and COLF groups were significantly regulated, as indicated by the GO enrichment analysis. The NF-κB signaling pathway was identified through KEGG enrichment analysis for further exploration of the mechanism by which COLFs affect macrophages. Additionally, Western blotting analysis indicated that COLFs could influence the activity of the NF-κB/MAPK signaling pathway via the TLR4 receptor, thereby modulating its anti-inflammatory function. Overall, our results reveal a novel role for COLFs as natural inflammation regulators and provide a theoretical and molecular basis for their development and utilization.