NIR-stimulated rGO-HAMC hydrogel enhances fracture healing through regulating B-cell signaling.

Bone fractures are frequently encountered in clinical practice and pose significant challenges, due to the high incidence of delayed healing or non-union. Reduced graphene oxide (rGO) stands out for its unique sensitivity to a wide range of light wavelengths, especially in the near-infrared (NIR) spectrum. In this study, we developed an approach to promote fracture healing using an rGO-HAMC hydrogel activated by NIR stimulation. In vitro experiments demonstrated that NIR-stimulated rGO hydrogel significantly enhanced osteogenesis in bone marrow stromal cells (BMSCs). In an in vivo mouse fracture model, the rGO hydrogel was applied to the fracture site, and NIR light was delivered transdermally, showing promising results in accelerating bone regeneration. These results demonstrate that NIR-stimulated rGO hydrogel significantly accelerates fracture healing, as evidenced by increased bone volume and trabecular thickness. Additionally, transcriptomic analysis revealed that pathways related to B-cell activation are implicated in the enhanced healing effects mediated by NIR-stimulated rGO hydrogel. These findings highlight the potential of the NIR-stimulated rGO hydrogel as an innovative strategy for bone regeneration, offering promising new avenues for the treatment and management of bone fractures.