A secondary metabolites produced by Streptomyces ssp. XY-R31 suppresses LPS-induced inflammatory responses through NF-κB, MAPKs, and HO-1 Pathways in RAW264.7 cells

Inflammation response is a complex physiological process and suppression of inflammation activated in macrophages induced by LPS is an important target for treatment of various chronic diseases. A crude extract produced by Streptomyces ssp. (R31 crude extract) which was isolated from a mangrove sediment showed a significant inhibitory effect in LPS-stimulated inflammatory response. In this study, R31 crude extract decreased the NO production dose-dependently. The release of IL-6 and IL-10 in macrophages were reduced upon pretreatment of R31 crude extract. In addition, R31 crude extract treatment inhibited the translocation of NF-κB and NFAT into the nucleus and the phosphorylation of MAPKs as well as AKT. On the other hand, R31 crude extract induced HO-1 expression in LPS-stimulated macrophage. Collectively, these findings indicate that R31 crude extract exhibited an anti-inflammatory effect and is a potential therapeutic candidate for the treatment of inflammatory diseases.