The Effect of COX-2 Inhibitor on the Expression of MMP-13 during Early Fracture Healing Phase in Rats

ABSTRACT

PURPOSE: This study investigated the effect of COX-2 inhibitor on the expression of MMP-13 in the healing process of fracture. MATERIAL AND METHODS: Adult Sprague-Dawley rats were divided into two groups of twenty five rats each. Unilateral femoral shaft fractures were created artificially under displacement in all two groups. COX-2 inhibitor was only given to the experimental group from the postoperative day 1. At 2 weeks after fracture the rats were sacrificed and the callus from each group was used for histologic examination and real time RT-PCR for MMP-13 expression. RESULTS: Histologically, proliferation of osteoblasts and formation of osteoid was less abundant in the experimental group. In real time RT-PCR, the mean expression of MMP-13 is 2.84+/-2.50 in the control group compared with 1.16+/-1.05 in the experimental group. CONCLUSION: In the early stage of fracture healing, COX-2 inhibitor suppress the expression of MMP-13.