Abstract:

Objective To investigate the biological mechanisms and feasibility of collagen/hydroxyapatite scaffolds for repairing articular cartilage and subchondral bone defects. Methods 45 New Zealand white rabbits were included. Full-thickness articular cartilage defect models were established in experiment and control groups and the biomaterial scaffolds were implanted in the experiment group. The animals were sacrificed in the 4th, 6th and 8th week after the operation respectively. Histological scores were performed by semi-quantity cartilage scoring system and the expressions of matrix metalloproteinases (MMPs)-2, 3, 9 and 13 mRNA in the synovialis were detected with RT-PCR. Results The repaired tissues were totally hyaline cartilages in the experiment group 2 weeks after operation and there were no repaired tissues in the control group. There were significant differences between these 2 groups in Wakitani scores (P<0.01). The activation and expression of MMP-2, 3, 9 decreased in the experiment group (P<0.05), but the activation of MMP-13 sustained and the expression of MMP-13 could be detected during the observed period (P>0.05). Conclusion The new biological scaffold can alleviate the inflammatory and protect the cartilages by inhibiting the expression of MMPS, which promote the reconstruction of articular cartilage in rabbits.

Key words: cartilage defect, biomaterial scaffolds, matrix metalloproteinases, rabbits