Anti-inflammatory properties of Morus bombycis Koidzumi via inhibiting IFN-β signaling and NLRP3 inflammasome activation

Morus bombycis Koidzumi (M. bombycis, Moraceae) has been used in Asian countries as a traditional medicine for the treatment of hypertension, diabetes, and inflammation-related disorders. Although its anti-inflammatory actions have been partly documented, scientific evidence involving its molecular mechanisms related to inflammasome activation signaling pathways remains unknown. Lipopolysaccharide-stimulated RAW 264.7 cells and bone marrow-derived murine macrophages were used to study the in vitro effect of methanolic extract of M. bombycis (MB) on inflammatory responses. A monosodium urate crystal (MSU)-induced peritonitis murine model was used to study the in vivo effects. MB attenuated the production of nitric oxide and interleukin-6, through the regulation of the interferon-β receptor signaling pathway. MB also inhibited IL-1β secretion via attenuation of NLRP3 inflammasome activation. Furthermore, MB inhibited MSU-induced peritonitis in the in vivo murine model. This study provides the key molecular mechanisms involved in the anti-inflammatory effects of M. bombycis, substantiating the traditional claims of its use in the treatment of inflammation-related disorders. [Display omitted]