Abstract: This study designed and synthesized an inorganic-organic composite Ce-Cur nanoenzyme using cerium chloride (CeCl3) and curcumin (Cur) as raw materials, with polyvinylpyrrolidone (PVP) as the dispersant. Systematic characterization of its microstructure and surface properties was performed using X-ray powder diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), zeta potential, and particle size analysis. In vitro antioxidant activity was evaluated via ABTS and DPPH radical scavenging assays, while DCFH-DA fluorescence probe-based assays assessed its ability to scavenge reactive oxygen species (ROS) within macrophages. Results indicate that the Ce-Cur nanozyme exhibits excellent antioxidant capacity, significantly reducing intracellular ROS levels (fluorescence intensity MFI decreased by 53%). CCK8 assays and live/dead fluorescent staining experiments demonstrated excellent cellular compatibility of the nanozyme. Real-time quantitative PCR (RT-qPCR), immunofluorescence, and ELISA analyses revealed that Ce-Cur nanozyme effectively suppressed LPS+IFN-γ-induced inflammatory responses. It downregulated mRNA expression and protein secretion of M1-type inflammatory cytokines TNF-α, IL-1β, and IL-6 (The M1 inhibition rates were 57%, 67%, and 82%, respectively.), while simultaneously promoting the expression of the M2 anti-inflammatory factor IL-10 (M2 growth rate reached 351%). These results indicate synergistic antioxidant and anti-inflammatory effects between curcumin and amorphous cerium oxide components, significantly regulating macrophage polarization from the M1 to the M2 phenotype. This study provides experimental evidence and potential strategies for the application of Ce-Cur nanoenzymes in immunomodulation and the treatment of related inflammatory diseases.

Key words:  Ce-Cur nanoenzymes；Macrophage；M1-type inflammatory factors；M2-type anti-inflammatory factors, Polarization