Anti-inflammatory effect of Chrysanthemum zawadskii, peppermint, Glycyrrhiza glabra herbal mixture in lipopolysaccharide-stimulated RAW264.7 macrophages

Abstract

The normal inflammatory reaction protects the body from harmful external factors, whereas abnormal chronic inflammation can cause various diseases, including cancer. The purpose of the present study was to investigate the anti-inflammatory activity of a mixture of Chrysanthemum zawadskii, peppermint and Glycyrrhiza glabra (CPG) by analyzing the expression levels of inflammatory mediators, cytokines and tran- scription factors in lipopolysaccharide (LPS)-stimulated Raw264.7 cells. A nitric oxide assay, ELISA, western blotting and immunofluorescence staining were performed to investigate the anti-inflammatory activity of the CPG mixture. Pretreatment of Raw264.7 cells with CPG inhibited the increase of inflammatory mediators (induc- ible nitric oxide synthase, cyclooxygenase-2 and IFN-β) induced by LPS. Additionally, it inhibited the production of pro-inflammatory cytokines (TNF-α, IL-6 and IL-1β). CPG suppressed LPS-induced phosphorylation of STAT1, AKT, Iκb and NF-κB. Furthermore, CPG inhibited the translocation of NF-κB into the nucleus. In summary, CPG could inhibit LPS-induced inflammation, which occurs primarily through the AKT/Iκb/NF-κB signaling pathway in RAW264.7 cells.