Abstract
Due to the differences in cell types, structural composition, and mechanical properties between articular cartilage and subchondral bone, developing effective integrated repair strategy persists as a major clinical hurdle. We constructed a novel scaffold by a three-dimensional (3D) printing and surface modification method for the potential application of simultaneously promoting bone and cartilage repair. MgAl-layered double hydroxide (MgAl-LDH) nanosheets were synthesized via the hydrothermal method and then modified on β-tricalcium phosphate (β-TCP) scaffolds. The prepared composite scaffolds exhibited a uniform microstructure, suitable compressive strength, and satisfactory biocompatibility. Attributing to the released bioactive ions, MgAl-LDHs-TCP effectively supported the proliferation and attachment of rabbit bone marrow mesenchymal stem cells and chondrocytes. Furthermore, 72MgAl-LDHs-TCP scaffolds obviously promoted osteogenic differentiation, provided deposition sites for calcium salt formation, induced the formation of alkaline phosphatase, and created favorable conditions for the early-stage and end-stage osteogenic differentiation of rBMSCs. Simultaneously, attributed to the released functional ions, the prepared composite scaffolds significantly enhanced the synthetic metabolism in chondrocytes and inhibited the expression of catabolism-related genes, playing an important role in protecting arthritis chondrocytes. Overall, such prepared scaffolds may have the possible application for the simultaneous regeneration of cartilage and subchondral bone defects.