Near-infrared Mo2Ti2C3 MXene gelatin-chitosan hydrogels with antioxidative, anti-inflammation activity for osteoarthritis treatment.

Knee Osteoarthritis (OA) is prevalent in older adults which eventually lead to disability. Current treatment only alleviates symptoms but does not cure the disease. Herein, we implanted Mo2Ti2C3 MXene gelatin-chitosan hydrogels into the osteoarthritis knee joint in mice and treated with 808 nm laser radiation. We investigated MXene hydrogel structure and near infrared radiation (NIR) effect on cell biocompatibility, cartilage matrix synthesis, reactive oxygen species (ROS)production and inflammation in vitro. In vivo anterior cruciate ligament transection (ACLT) OA model treated with MXene hydrogel and NIR exhibits delayed osteoarthritis progression with fewer osteophyte and wider articular space, reduced cartilage lesion, lower Osteoarthritis Research Society International (OARSI) score, higher glycosaminoglycan (GAG) content, higher number of aggrecan and col-II positive cells. Mo2Ti2C3 MXene hydrogel with NIR reduced M1 macrophage related IL-1β and IL-6, increased M2 macrophage related TGF-β and IL-10 in cartilage in OA. Mo2Ti2C3 MXene hydrogel with NIR attenuated ROS and chondrocytes apoptosis in vivo. Mo2Ti2C3 MXene hydrogel may provide a new strategy in treatment of OA.