Ergothioneine-Derived Carbon Dot Nanozymes Alleviate the Oxidative Stress Microenvironment to Delay Intervertebral Disc Degeneration.

Nucleus pulposus cells (NPCs) age mainly because reactive oxygen species (ROS) build up too much. Excess ROS is associated with intervertebral disc degeneration (IVDD). In this study, we prepared ergothioneine-derived carbon dots (EGT-Fe-CDs) as an antioxidant nanozyme. EGT-Fe-CDs showed good biocompatibility, superoxide dismutase-like and catalase-like activities, and high total antioxidant capacity. In H2O2-treated NPCs, EGT-Fe-CDs reduced cell damage. Local EGT-Fe-CDs treatment also reduced degeneration in the animal model, based on imaging, disc height index (DHI), and Pfirrmann grade. EGT-Fe-CDs also reduced mitochondrial damage associated with excess ROS. They slow down NPC ageing and help control IVDD. Based on these characteristics, the nanozyme could be a useful option for clinical therapy in the future.