Neobavaisoflavone ameliorates LPS-induced RAW۲۶۴.۷ cell inflammations by suppressing the activation of NF-κB and MAPKs signaling pathways

Objective(s): Neobavaisoflavone (NBIF) is an isoflavone isolated from Psoralea corylifolia L. It can effectively regulate the redox state as a natural anti-oxidant and show some anti-inflammatory activity. However, its molecular mechanism is poorly studied. In this study, RAW۲۶۴.۷ cells were treated with lipopolysaccharide (LPS) to investigate the anti-inflammatory activity and potential NBIF mechanism.Materials and Methods: RAW۲۶۴.۷ cells were treated with LPS (۶۲.۵ ng/ml) and exposed to different concentrations of NBIF (۰.۰۱, ۰.۱, and ۱ μM) for ۲۴ hr. Inflammatory cytokines of RAW۲۶۴.۷ cells were measured by the Griess method, ELISA, and western blot. Phagocytosis of RAW۲۶۴.۷ macrophages was measured by FITC-dextran uptake assay. The phosphorylation protein expression levels of MAPKs (JNK, p۳۸, and ERK), NF-κB p۶۵, IκBα, and IκB kinase were analyzed by western blot. The results were analyzed using one-way ANOVA with Tukey’s multiple comparison test.Results: NBIF significantly inhibited NO and ROS production by down-regulation of iNOS and COX-۲ protein expression. Additionally, the amount of release and protein levels of inflammation cytokines IL-۶, IL-۱β, and TNF-α were significantly decreased by NBIF. Moreover, FITC–dextran uptake assay by flow cytometry presented that NBIF significantly enhanced the phagocytic capacity of RAW۲۶۴.۷. Mechanistically, NBIF significantly down-regulated MAPK activation and inhibited the nuclear translocation of NF-κB p۶۵. Conclusion: The present study demonstrates that NBIF inhibited inflammation and enhanced the phagocytic capacity of RAW۲۶۴.۷ cell-related MAPKs and NF-κB signaling pathways induced by LPS. These findings suggest that NBIF may have clinical utility as an anti-inflammatory agent.

Keywords:

Inflammation , MAP kinase signaling - system , Neobavaisoflavone , NF-kappa B