ABSTRACT
Inflammatory bowel diseases (IBD) are the incurable chronic recurrent gastrointestinal disorders and currently lack in safe and effective drugs. In this study, patchouli alcohol, a main active compound of traditional Chinese herb patchouli, was developed into biomimetic liposomes for macrophage-targeting delivery for IBD treatment. The developed lactoferrin-modified liposomes (LF-lipo) can specifically bind to LRP-1 expressed on the activated colonic macrophages and achieve cell-targeting anti-inflammatory therapy. LF-lipo reduced the levels of inflammatory cytokines and ROS and suppressed the MAPK/NF-κB pathway. LF-lipo also suppressed the formation of NLRP3 inflammasome and the consequent IL-1ß activation. LF-lipo showed improved therapeutic efficacy in a DSS-induced colitis murine model, evidenced by the reduced disease activity index, the improved colon functions, and the downregulated inflammatory cytokines in the colon. LF-lipo provided an effective and safe macrophage-targeting delivery and therapeutic strategy for addressing the unmet medical need in IBD management.
ABSTRACT
Macrophages, an important component of the innate immune response, are a key regulator of intestinal microenvironment homeostasis. These cells essentially contribute to chronic inflammatory diseases due to their strong plasticity. As is known, ulcerative colitis (UC), a chronic inflammatory disease, is closely related to immune dysfunction. A growing body of evidence suggests that the macrophage is a promising drug target for modulating the intestinal immune systems and regulating the inflammatory microenvironment, thus alleviating the inflammatory responses in UC. The macrophage-based therapy strategies for UC are still at an emerging stage. The advanced drug delivery systems can improve the macrophage-based therapy. This article will review the molecular mechanisms related to macrophage polarization and the interactions between signaling pathways that regulate the pathogenesis of UC and summarize the macrophage-based nanotherapeutic strategies in UC.