The role of matrix metalloproteinases in early and late gonarthrosis manifestations

Abstract

The aim of this research was to study the specifics of the matrix metallopeptidase system in early and late gonarthrosis (GA) manifestations. Material and Methods — 37 patients of the main group (0-I stages of GA), 30 patients of the comparison group (III-IV stages of GA) and 30 healthy individuals of the control group underwent sonography and T2-relaxometry of their knee joints. The 24-h excretion of urinary C-telopeptide fragments of type II collagen (СTX-II) as well as serum concentrations of matrix metalloproteinases-3 and -8 (MMP-3, MMP-8), and tissue inhibitor of metalloproteinases (TIMP-1) were also registered. Results — We detected increases in urinary СTX-II to 3.9 [2.5; 4.5] mg/d, MMP-8 to 364.7 [215; 434] pg/ml and TIMP-1 to 806 [559; 1157] pg/ml in the main group; to 9.7 [6.8; 10.2] mg/d, 579 [463; 663] pg/ml and 1256 [1029; 1330] pg/ml in the comparison group. The presence (p=0.04) of strong positive correlation (R=0.7) between the 24-h urinary СTX-II excretion and the change of MRI-signal characteristics for the areas of hyaline cartilage under the heaviest load on knee joints T2 relaxometry evidence was observed as well as the presence (p=0.001) of strong positive correlation (R=0.7) between MMP-8 and 24-h urinary СTX-II extraction. In early GA stages a strong positive correlation (R=0.6) was observed between MMP-8 and TIMP-1 (p=0.04) as well as 24-h urinary СTX-II excretion and TIMP-1 (R=0.5) at p˂0.001). Conclusion — Type II collagen degradation with MMP-8/TIMP-1 imbalance is one of the relevant mechanisms of the hyaline articular cartilage extracellular matrix disorganization in early and late GA evidences. The rearrangement of correlations between MMP-8 and TIMP-1 indicates the change in interaction mechanisms for GA proteolytic enzyme system components.