Effects of exercises on levels of cartilage biomarkers in serum and synovial fluid / 解放军医学杂志

ABSTRACT

Objective To explore the significance of such biological markers as cartilage oligomeric matrix protein (COMP), matrix metalloproteinases-1(MMP-1), matrix metalloproteinases-3 (MMP-3) and tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) in serum and synovial fluid to evaluate early motional injury on knee joint cartilage induced by different modes of training. Methods Twenty adult dogs were randomly divided into three groups, i.e. common training group (n=8), short intensified training group (n=8) and control group (n=4). Magnetic resonance imaging (MRI) examinations were performed regularly (0, 2, 4, 6, 8, 10 weeks) to investigate the changes in the knee joint cartilage, while the concentrations of COMP, MMP-1, MMP-3 and TIMP-1 in serum and synovial fluid were measured by ELISA. Results It was revealed by MRI that the motional injury to knee joint cartilage occurred both in common training group and short intensified training group 2 weeks after training with different intensity, with severest injury occurring during 4~6 weeks after training, and then subsided gradually. The concentrations of COMP, MMP-1, MMP-3, TIMP-1 and MMP-3/TIMP-1 in serum and synovial fluid elevated in various degrees during training period with the lapse of time. Generally, the concentrations of MMP-1, MMP-3 and MMP-3/TIMP-1 in short intensified training group were lower, while that of COMP was higher, than that in common training group. The results suggested that the possibility of incurring articular injury in short intensified training group was lower than that in common training group, while the possibility of repairing the injury was on the contrary. Furthermore, the changes in levels of biomarkers in both serum and synovial fluid showed a close correlation. Conclusions Intensified training may result in moulding reconstruction better than the common training did. A combined determination of several biomarkers could be more sensitive than MRI examination on predicting the injury and repair of articular cartilage and on monitoring the course of illness. Therefore they are valuable for clinical application.