Red emissive carbon dots Self-Cascading antioxidant nanozymes combine with anti-miRNA-155 for accurate monitoring and ameliorating rheumatoid arthritis

Abstract

Accurate monitoring and effective antioxidant treatment strategies are highly desirable in rheumatoid arthritis (RA) amelioration. Herein, cerium (Ce) and selenium (Se) co-doped carbon dots (CS-CDs) integrated superoxide dismutase (SOD)-like and glutathione peroxidase (GPx)-like self-cascading catalytic activity are engineered. In this self-cascading nanozymes system, Ce active center catalyzes ·O2− to H2O2 by mimicking SOD, and the adjacent Se component sequentially decomposes the H2O2 by mimicking GPx, achieving enhanced catalytic and superior reactive oxygen species (ROS)-scavenging activities. CS-CDs further load cyanine-5 (Cy5)-labeled anti-miRNA-155 to realize macrophage subphenotype identification via miRNA-155 ratiometric imaging for RA accurate monitoring, and regulate the polarization of pro-inflammatory macrophages for synergistic RA amelioration. Comprehensive in vitro and in vivo experiments validate the advanced RA monitoring and therapy performance of the self-cascading nanozymes. This work not only offers a rationally designed self-cascading nanozyme with simple structures and intriguing ROS-scavenging capacity, but also opens up a strategy for accurate RA monitoring and synergistic amelioration.