Amelioration of the rheumatoid arthritis microenvironment using celastrol-loaded silver-modified ceria nanoparticles for enhanced treatment.

Rheumatoid arthritis (RA) is characterized by elevated levels of reactive oxygen species (ROS) and a persistent inflammatory microenvironment dominated by M1 macrophages, both of which contribute to disease progression. To address these pathological features, we developed a core-shell nanoplatform consisting of silver-modified ceria nanoparticles loaded with celastrol (Ag-CeNP@Cel). This nanoplatform significantly enhances the water solubility of celastrol and reduces its hepato-renal toxicity by enabling passive accumulation in inflamed joints. The silver-modified ceria nanoparticles synergistically combine with celastrol to scavenge excess ROS and reprogram M1 macrophages into M2 macrophages, thereby mitigating inflammatory responses and improving the rheumatoid arthritis microenvironment (RAM). Ag-CeNP@Cel exhibited robust therapeutic efficacy and safety in preclinical models, presenting an innovative approach to RA treatment by integrating ROS elimination with macrophage modulation to ameliorate inflammatory microenvironment. This study underscores the potential of Ag-CeNP@Cel as a promising therapeutic strategy for RA management.