Phillygenin inhibited LPS-induced RAW 264.7 cell inflammation by NF-κB pathway

Inflammation is a common pathological phenomenon when homeostasis is seriously disturbed. Phillygenin (PHI), a lignin component isolated from Forsythiae Fructus, has shown a good anti-inflammatory effect. However, the mechanisms of PHI on anti-inflammation have not yet been systematically elucidated. In this study, the lipopolysaccharide (LPS) - induced RAW264.7 cell inflammation model was established to investigate mechanisms of PHI on inflammation. The effect of PHI on the release of IL-1β and PGE2 inflammatory factors induced by LPS was detected by ELISA, and the mRNA expressions of IL-1β, IL-6 and TNF-α were detected by RT-qPCR. Proteomics studied the signaling pathways that might be affected by PHI and molecular docking technology was subsequently used to study the possible targets on proteomic screened pathways. Western blot was performed ultimately to detect progressive changes in protein expression on the related pathway. Our research showed that PHI significantly inhibited the robust increase of IL-1β and PGE2 and lowered the transcriptional level of inflammatory genes including IL-6, IL-1β and PGE2 in LPS-stimulated RAW264.7 cells. Proteomics results indicated that PHI was involved in the regulation of multiple signaling pathways. Molecular docking results indicated that PHI had an affinity for most proteins in NF-κB pathway. Western blot analysis proved that PHI inhibited LPS-induced NF-κB pathway activation. On the whole, PHI inhibited the activation of NF-κB pathway, thereby inhibiting the expression of related inflammatory genes and the release of cytokines, and showed a remarkable anti-inflammatory effect.