Effect of Paeoniae Radix Rubra (Paeonia lactiflora Pall.) extract on mucin secretion, gene expression in human airway epithelial cells

Ethnopharmacological relevance: Paeoniae Radix Rubra (PRR), the root of Paeonia lactiflora Pall., is a traditional Chinese medicine which has the effects of regulating various inflammatory diseases, treating blood stasis, and enhancing blood circulation. Aim of the study: This study examined whether Paeoniae Radix rubra extract (PRRE) and Paeoniflorin (PF) affect mucin production, gene expression including MUC5AC, and protein expression related to the ERK pathway induced by TNF-alpha from human airway epithelial cells. Materials and methods: NCI-H292 cells induced by TNF-alpha were treated with each agent. MUC5AC mucin gene expression and mucin protein production were measured by reverse transcription polymerase chain reaction, staining, and enzyme-linked immunosorbent assay. Western blot was used to investigate the cell signaling pathways. Results: PRRE and PF inhibited the production of MUC5AC mucin protein and gene expression in TNF-alpha-induced H292 cells. In Western blot, PRRE was involved in protein expression related to the ERK pathway. Conclusions: Overall, PRRE effectively inhibited the MUC5AC, and inflammatory cytokines expression caused by TNF-alpha, which was closely involved in the ERK pathway. PRRE may have the potential for treating mucus pro-ducing respiratory inflammation.