Zwitterionic-based cyclic brush polymer nanomicelles with improved lubrication and antioxidation properties

Osteoarthritis (OA) is a degenerative bone and joint disease characterized by cartilage degradation and an inflammatory environment. Consequently, strategies aimed at remodeling the damaged joint microenvironment by concurrently enhancing lubrication and alleviating inflammation are essential for improving therapeutic efficacy. Herein, we designed multifunctional cyclic brush polymer (CP) nanomicelles composed of surface-grafted zwitterionic poly(sulfobetaine methacrylate) (PSBMA) brushes and a hydrophobic core of PHEMA. Benefiting from the unique cyclic brush topology and hydrated lubrication properties of PSBMA, the CPs exhibited effective lubrication. Tribological and wear tests showcased the CPs significantly reduced the coefficient of friction and surface wear under shear forces. Furthermore, the CPs served as nanocarriers for encapsulating the anti-inflammatory drug resveratrol (RSV) through hydrophobic interactions, serving as drug-loaded nanomicelles CP@RSV. In vitro studies indicated that CP@RSV exhibited excellent cytocompatibility, effectively eliminated reactive oxygen species (ROS) in cells and reversed mitochondrial dysfunction, thereby modulating the oxidative stress microenvironment. In conclusion, CP@RSV integrates enhanced lubrication with antioxidation properties, representing a promising strategy for the treatment of OA.